The Best of MySQL Forum

I have tagged many of the better forum threads. 'Better' is based on how good I thing the answer was. (<bias> I wrote many, but not all, of the better answers. </bias>)
-- Rick James, MySQL Geek

The Best of the Best

Thread Tags
Function and indexes index
is good have single index an composite index on same field compound index, index, LIKE
GROUP causing Using Temporary Using Filesort summary tables
Question about indexes index, PRIMARY KEY
Optimize table and fragmentation defragmentation, OPTIMIZE TABLE
Optimize Inner Join With WHERE BETWEEN dates index, optimizer
Slow query. Why is it slow? index examples
Multiple Tables Split By Date big
When to use separate tables. phone numbers
Jet Profiler says I'm slow.... pagination
Does LIMIT 1 without ORDER BY ID bring the record with minimum ID? index, InnoDB
Problem with a query performance INDEX, not using index
User defined fields in a schema EAV, JSON, key-value
Large Table Architecture summary
Thai Characters display as ??? charset
any cheat-sheet style documents? password, root
random sorting - what is the quickest method? random
Data model metadata design and data driven joins ER, key value
How much space take each column in table datatype size
Efficient MySQL for pagination of large amounts of data on website pagination
next/previous on a date select query left off
index performance on "limit" condition index, limit
Trying to retrieve data where a variable is in an array commalist
adding index to a table ALTER
Slow Mysql optimizer slow
New to InnoDB (want to convert from MyISAM) myisam vs innodb
Selecting max for each day top N
JOIN vs Denormalize table vs Vertical partition normalize, vertical partition
HELP! making choises on Performance - Storage engine - Caching myisam vs innodb
select limit records from 600000 records rand
Partitioning with range(to_days) issue partition, summary
INNO DB performance problems with temporary tables join, union
limiting rows returned group by trick
DATETIME vs. INT(11)? index, TIMESTAMP vs DATETIME
Memory mirror for read-only tables?
Top n Scores top N
Slave is lagging from master replication lag
How does group by algorithm works? group by trick
Preferable Index Length index
How to create partition on existing table? partition
User password being modified as a result of grant statements? grant
MySql 4.1 optimization search poor performance group by, limit
How do I combine 3 queries into one LAST_INSERTED_ID, on duplicate key
Deadlock occuring since setting a unique index. on duplicate
Advice on redundant indexing index
Select * from MyISAM table returns PK order / filesort order 30%, range, table scan
Key_Buffer_Size key_buffer
linked data key value, rdf
Optimising max_heap_table_size & tmp_table_size memory, tmp tables
Database Design for huge set of data data warehouse, summary
Need Help - Server was hacked login, root
Counters summary
image display problem from mysql database image
Converting latin1 charset to utf8 charset
using GROUP_CONCAT group by
Performance LONGTEXT / LONGBINARY 768, blob, parallel
Column for mutiple and not-predefined values comma
Unsure about query... random column? group by
Performance with select query that joins two tables one with 45MM and another with 12MM classic
Solving table locking issues locks, summary tables
Alternative to FOUND_ROWS() count, found_rows, innodb, pagination
Having tough time with spanish/catalan characters in my PHP/MySQL app charset
Processor at 99.9%, memory at 5%. Configuration help? key_buffer
random reads filing cabinets, myisam, perf
Design approach for summary table by 3 items summary
Query performance question (using index slows down?) pagination
How to scale MySQL Cluster to support PB storage big, petabyte, sharding
Query performance on database with joins pagination
Complex Select with Min/Max Syntax group by trick
problem with concat() distinct() min() and GROUP BY group by
Your PHP server doesn't have the MySQL module loaded or you can't use the mysql_(p)connect functions php install
Storage capacity limits
InnoDB log group capacity error memory, text, varchar

Lots more

Tags are alphabetical, but it may help to use the browser's search. Threads with multiple tags show up multiple times.
Tag Thread
1005 Soln. for MySql 1005 (Can't create table)
ERROR 1005 (HY000): Can't create table 'Azienda.#sql-697_c9' (errno: 150)
10060 Solotion of errno: 10060(1)
Connect remote server using ODBC connection
10061 Running MySQL with no Internet
Can't connect to Mysql 127.0.0.1 (10061), before never had the problem. What coudl have caused that?
1016 Replication error?
1067 How do I change this table to get it to load
Erroe #1067
10x Slow Query stuck on "Sending Data"
12 Got error 12 from storage engine
1206 Question about merging big tables?
121 Foreign Key Error 121
1236 Replication fun
134 error 134
1364 MYSQL Error n4 1364 (authentication string no default) while configuring
1366 string error data type and Character set for DUTCH language
139 Got error 139 from storage engine
150 Soln. for MySql 1005 (Can't create table)
errno: 150 - foreign key constraint was not correctly formed
ERROR 1005 (HY000): Can't create table 'Azienda.#sql-697_c9' (errno: 150)
Help! Foreign Key error from SQL generated by workbench modelling
ERROR 1005: Can't create table (errno: 150)
Alter table add foreign key causes can't create table error
16kb Estimate table size
2 ranges Index with two date fields using comparison operators
2-field index problem for selecting range of date between 2 dates
2002 ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (61)
MySQL error, please help
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
MySQL startup - ERROR 2002 (HY000)
Could socket failure be related to InnoDB errors?
how do you fix error 2002
MySQL Error Nr. 2002
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
2006 Running Large scripts from command line
2d Simple query seems to be ignoring date index
3 machines Multi-Master replication in MySQL 5.1
30% Select * from MyISAM table returns PK order / filesort order
4g MAX_ROWS on Partitions
5.5 regression performance degrades. why???
50x index is not used why?
5x how to optimize this query
64-bit 32-bit BIGINT value
768 Is BLOB stored in InnoDB buffer pool?
Performance LONGTEXT / LONGBINARY
:= Using a Parameter in Load Data Infile Command (Instead of direct filename)
compare two rows in the same column
RANK() emulator?
Trying to Update Table with Rank...
accents accent sensitivity in fulltext search
Searching with accented words
access Configure Database
Access 97 to MySQL
Microsoft Access & mySQL
Database Import
Db access/privileges philosophy
MS Access transfer to MySQL on host server
Converting Access to MySQL
help please
acid COUNT(*) very slowly in large InnoDB table
what's the purpose of InnoDB
How does MySQL ensure ACID nature of transactions ?
ad Database Sharding at Netlog, with MySQL and PHP
add pk Adding primary key afterwards
ai Error Duplicate entry - Master-Slave replication
aliases speed of query/can index help?
allow_invalid_dates Load data infile not working
alter Table fragmentation and optimization
Reverse Index columns
How to clean up database after deleting records
enable keys, force sort, not keycache
Will increaseing table size affect current data?
Large table designissue
Require suggestion for changing character set in Master master replication setup
adding index to a table
Performing table inserts/selects while a alter-table query is running?
Migrating from latin1 to utf-8
Adding columns to live tables
does innodb table need 'optimize table'?
alter enum Need to change datatype for an enumerated field
alter on dual master Alter table with million of records - estimate how long does it take
alter table Index re-creation after composite primary key change
alter via copy seeking for better solution to change indexed column size
Alter large table(MYISAM)
Partitioning and multiple threads
analyze ANALYZE TABLE not working correctly
Mysql does not use index, even if example is trivial?
and2union Index structure
apparmor ubantu Problem with LOAD_FILE
application lock Table Row Locking
aramaic Best collation to use for ancient languages
attributes Theoretical Database Table Structure
audio player MySQL + PHP Audio Reference
audit trail Audit Trail Help...again
Snapshot Table -- over the long run
auditing changes via replication
upon retrieving the last insert id get the table name?
auditing How to audit entire database?
auto-normalize Importing a Tab-Delimited file into multiple tables
autocommit turning autocommit off by default
Replication Slave update question
autocommit=off How to identify which connection has locked a particular table
autocomplete understanding the best design method for links table
autoextend innodb_data_file_path
Automatic Extension Question
auto_increment AUTOINCREMENT & ROLLBACK
autoincrement without primary key
auto_increment behaviour
AUTO_INCREMENT value increases by powers of two after INSERT ... SELECT
insert ignore ... auto increment value
Automatic field in a table
Suggestable Engine
autoincrement id missing when i do load data local into file
MySQL Workbench 5.2.35: Error 1064: You have an error in your SQL syntax
Resetting Auto Increment?
table with multiple primary key
auto_increment gap Problem with "false" increment in InnoDB using a table with UNIQUE constraint
auto_increment gaps Can Autoincrement find the next free number ?
b*tch Is this database structure correct? Please help oh wise ones :)
back tics how to drop database named as database
backslashes Correct syntax to search for backslashes "\"
backup mysql with innodb and myisam
MySQL Replication
Replicating a big db
MySQL Enterprise Backup Remotely
Replication setup (for the first time)
backup options How can we ensure if mysql backups are consistent
backup replay restoring a DB from slave to the master in a replicated 2 node environment
bad design pattern select top x with a union
banking Ensuring data integrity
batch insert Batch Insert
batch normalization Alternate for Varrays in Oracle
batched inserts How to improve the insertion speed
how to update with array (containing arrays) into table? or inserting? hot to combine with escaping?
bbwc Mixed engines within same database
benchmark Anyone know where a recent MySQL benchmark vs others can be found?
benefical subquery Larger than expected tmp files querying InnoDB format database
best practice Real-world DB schema
between Slow query
big About performance for Database of millions of records
Questions about performance for huge table (100M+ rows)
A lot of rows for a very specific task
How to scale MySQL Cluster to support PB storage
use index on a view
Up to 1 million rows Performance + Design Help
MySQL Appropriate for 1T- 5T DW ?
Multiple Tables Split By Date
bigint Performance Issue
bind-address ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
binlog Binlog not being updated...
DRBD and Binary logs
binlog off end Could not parse relay log event entry
binlog-do-db slave replicates databases it should not
binlog-row-event-max-size ERROR 1153 (08S01) at line 356771902 in file: 'mysqlmulti-bins.sql': Got a packet bigger than 'max_allowed_packet' bytes
blob slow queries and high % of wait I/O
Performance LONGTEXT / LONGBINARY
MySQL blob performance
STORE FINGER PRINT IN MYSQL
block splits Row size computation
book Kimball book recommendations & Schema question
Online/Free Book Recommendations
Is MySQL the tool I need?
Getting started, need WINDOWS information
book recommendations Reading list suggestions for query skills
Any tips for an MS SQL DBA trying to break into MySQL?
Tips to close a reference book
boolean Strange result from DELETE query - can anyone explain?!
brag Queries to limit only this month and next month
btree Is this model correct?
COUNT(*) very slowly in large InnoDB table
Index re-creation after composite primary key change
bucketizing Counting occurences of data falling betwen a series of limits (buckets)
buffer INSERT/UPDATE within transactions (autocommit=0)
buildins Why does "in ()" give syntax error?
bulk Bulk collect
Best primary key or index
bulk insert Bulk Insert Prepared Statement
bulk_insert_buffer_size Importing huge dump files into mysql
c api Which strategy is better to traverse a big table?
cache Basic Standards of Mysql server variable setting
caches re writing database
Linking to a LUT more than once
cannot connecct Unable to connect to database: Can't connect to MySQL server on '[database server]' (4)
canonical string Charset and Collation Question
case range Optimizing a Query on a Very Large Table
changelog How much data to save
auditing changes via replication
changes Database upgrade character column sizes may have changed
char vs int Best primary key or index
char vs varchar CHAR vs VARCHAR
Query to find values that are the same in multiple tables
char(0) What is quicker for searching out of these two?
character set filename How to get database encoded name in mysql 5.6
charset Problem inserting german and french characters
Having tough time with spanish/catalan characters in my PHP/MySQL app
Can replicating between versions cause crashed tables?
Converting latin1 charset to utf8
Weird utf-8 encoding problem using webserver that does not occur in command line client
cannot change character set
MYSQL doesn't 'see' accents
Encoding problem...
connection collation
Thai Characters display as ???
chcp Character set for French Candian ?
chcp 65001 Proper display of special latin1 characters in Powershell / MySql client ?
checksum CHECKSUM TABLE on InnoDB
chinese collation Chinese sorting and filtering on an table with charset UTF-8
chinese regexp how to retrieve only Chinese text from a table?
chunking big operation optimising a create table as select
chunks How to process very large result set from a dynamic cursor
circular mysql very slow after million insert/delete
cjk Asian language problems
classic Any way to optimize join to find rows without conditional foreign rows?
Performance with select query that joins two tables one with 45MM and another with 12MM
I have queries that sporadically take a very long time
Portal Database design help
3 Table Join (indexed) results in where-temp-filesort
JOIN, LIMIT, ORDER performance problems
clone slave replication - slave copy - unclear points
Moving dbs to new server
cloud partioning question
cluster Query optimization question
MySQL training on Cluster and High Availability
collation Unproper order of sorting in utf8. Collation?
"Duplicate entry" error using utf8_unicode_ci
Will changing Default Collation on live BSD box cause any problem?
A tip: Avoiding implicit charset matching errors
Can someone please explain this misbehavior?
collation benchmark Case sensitive vs non case sensitive performance
collation on sp Illegal mix of collations
combining diacriticals Searching database for strings with Swedish characters
comma search comma separated db column
Split Values by comma and Check in another Table?
Column for mutiple and not-predefined values
Iterating through SQL table
parse by delimiter and search a data field?
Setting up some new tables
arrays or joins for multiple values?
comma-join "In" Statement Returning 6 Records…overall SQL statement returns 22
commalist PREG_Match?
Trying to retrieve data where a variable is in an array
Having an argument about table design
commalist normalization Need Help W/ Query
commandline error logging
complex Slow SELECT on two tables
compound gt Showing recordsets from tables with one (main table) to many (secondary table) relationship
compound index Range on primary key using secondary index.
Index on Datetime Col is not used When Where Clause combines two or more predicates
Multi-Column indexes
is good have single index an composite index on same field
computer science Delete Query
concat CONCAT Dates returning "BLOB" or '?'
conditional average sum and display issue
connections mysql max_connections
Database Pool Size
Site closes when two many connections
consecutive values Highest interval between two date same table
construct queries Basic update statement
continuous compound index Newbie question about correct settings to achieve better performance
conversion Mixed encoded DB Latin1 & UTF8
convert_tz converting timezone for data in specific table
cores The result of MySQL's high concurrency and very large data performance benchmark.
InnoDB Plugin Version 1.0.3 for MySQL 5.1.30/31/32 Released
Maximize MySQL Performance on DBT2 Benchmark with Virtualization Technology on T5240 Server
Something awfull with latest mysql on latest FreeBSD
Help make my big new server fast
Intra-Query Parallelism in MySQL Server
MySQL + 2 x Intel Xeon (6 cores) performance problem
Queries on MyISAM
Why does MySQL's performance decrease when queries are executed in parallel?
count Alternative to FOUND_ROWS()
COUNT(*) very slowly in large InnoDB table
any faster select count(*)
Slow queries with very large table
count the disk hits is it good add 3 index on a table with 30,000 insert in every 15 minutes?
count(*) caching count(*) speed in InnoDB
covering index Strange performance with JOIN/COUNT
cp850 Characters not getting stored
cpus MySQL 20x faster on RHEL 4 over Solaris 10?
crash Replicating server has died
critical read separate the Query and direction
Three Node Replication (US West, US East and Europe)
MySQL Master(Active) - Master(Active) Replication
csv Export Recordset query to a file nightly? Ubuntu and MySQL
current_user Can see Databases can't see tables
cursor Cursor usage with Prepared Statements
custom collation Problem with LIKE on index over custom utf8 collation, 5.0
dag Unary many-to-many relationships
data directory data file location
data masking Tools for Scrubbing Entire Mysql Database
data models Car Parts Catalogue Database design
data warehouse Kimball book recommendations & Schema question
Online/Free Book Recommendations
Slow Inserts
Database Design for huge set of data
Inserting 5000 samples per sec in real time
mysql TABLE tuning and performance
Query optimization or better table design?
innodb or myisam for logging
MySql table disappears at random after multiple TRUNCATE queries
database One big DB or two not-too-big DBs? FKs across DBs are slower?
database layer how to upgrade database schema in M-M environment
datatype size Estimating disk space required for MySQL DB
Confused about integer disk space
Estimating Index Size on Innodb Tables
How much space take each column in table
datatype storage how table rows are stored at the file level
physical bytes
data_free file_per_table=1 question
fragmentation in innodb index
data_length Automatic Extension Question
date UPPER with substring is not working
Query Question
MySQL Date Query issue
how to convert timestamp value to string in MySql
date modulo Grouping by hour, day, weekday, week, month and year
date range Query taking a lot of time if there is no record in table
date reformat Casting Varchar to a date
datetime Time series database design
Calculating TIME ELAPSED SINCE in days OR hours OR minutes
missing data after partitioning - bug?
datetime in partition let table grow for two months then delete first month
datetime vs timestamp let table grow for two months then delete first month
store SET time_zone as part of a VIEW statement
daysequence Query results from one table against a list created by another
db stats Deployment Statistics....
dbd dbd::mysql not in ppm on windows
deadlock mysql_ping before transaction commit
deadlock vs lock_wait_timeout hard to test select for update scenario
deadlocks lock block deadlocks
decimal Is it possible to get MORE results by adding an AND clause to a SQL query?
size of Decimal(18,4)
Math function logarithm
default How do I change this table to get it to load
Should I add a default value for a field that is set to NOT NULL
definer View problems when updating to 5.5 from 5.1
defragmentation Optimize table and fragmentation
delete mysql very slow after million insert/delete
Statement/row questions
would like best table/index structure advice?
Performing multiple updates and selects
Very slow DELETE, UPDATE, INSERT on a new server
CPU Usage during DELETE and OPTIMIZE
MYsql getting crash
Cursor usage with Prepared Statements
Replication lag when no primary key on InnoDB
delimiter error using divide operator in function in mysql 5.5.9
delta Query to find difference between data
design Simple Database Design Problem
diff need help with cross referenced tables
dimensions Optimizing a query so that the smaller table is handled first
dims appropriate database design and query
directory structure Changing Data directory
disaster recovery Mysql SAN Related Scenarios
disaster recovery topologies How to configure multiple instances on 2 hosts?
disk hits delete timing-feasible?
disk usage Old databases that are no longer required
dissect explain optimize request with order by and limit
distinct distinct vs. group by
dll Fatal error: Call to undefined function mysql_connect() in C:\Program Files\Apache Group\Apache2\practice\testsql.php on line 17
Apache/MySQL/PHP Problem
dns Slow Connection
How to troubleshoot slow response from MySQL
double MySQL Workbench 5.2.35: Error 1064: You have an error in your SQL syntax
double encoding Character encodings issues with php, mysql, apache
fulltext search with utf8 characters (umlaut) with 5.1
double press Unwanted multiple inserts: Should I use insert or replace into?
double range Optimizing a query so that the smaller table is handled first
drbd DRBD and Binary logs
drupal temp table or query for API
dual master MySQL Master/Master Replication
MySQL settings for multiple server setup
MySQL & SAN
Replicating server has died
What is Best solution for DR and 24*7 using two identical systems, cluster is not available here(hw)
Multi Master and Slave MySQL servers
Is this a suitable plan
Masters in HA and slaves in LB
Multi-master & Multi data-paths
Replication & failover with 4 servers
Can anyone give an advise in Multy-master structure
Replication after dump
Mysql 2 server replication setup with fail over
dual master maintenance Performance maintaining a live database
dual master setup Master database crashed
Solving problems with mysql replica
dump take incremental backup
dump master re syncing a broken replicatoin
duplicate key Error Duplicate entry - Master-Slave replication
eah disaster RE: Academic Paper
eav Searching by using an index table, efficient queries?
How to speed up Query with WHERE AND/OR, with Subqueries using IN
Different data types
User defined fields in a schema
edge list relationship query question
either but not both Compare two tables
encryption Building Memory Table from AES Encrypted Physical Table
entities Simple Database Design Problem
Circular reference
Database Structure Help
Learning Management System MySql Database design
enum ENUM columns and blank values
using enum as means of compression
<char dimension with charset UTF8>
enum alternatives Poblem with a create table Query
enum trick Correcting spelling errors in an ENUM definition
eq_range_index_dive_limit Optimizer executes inperformant subquery first
er Query Performance Problem
Modeling and Normalizing
Searching by using an index table, efficient queries?
school exercise I am suck on
Database efficiency question
Data model metadata design and data driven joins
Simple Database Design Problem
Circular reference
Database Structure Help
DB structure - Managing a collection of books
My First Database (HELP)
Learning Management System MySql Database design
Designing a forum - general design logic question
Lookup Table with Optional Fields? Null primary key for blanks?
Problem creating table with 2 primary keys
erd ERD Design HELP!
error -1 got error -1 while reading table 'tablename'
error 108 InnoDB: File (unknown): 'flush' returned OS error 108. Cannot continue operation
error 150 query not running
#1005 - Can't create table (errno: 150)
error 24 Replication error?
escaping delete query doesnt work with php
replacing (escaping) unescaped apostrophes already in mysql
"#" symbol inside text of databse
How do I assign unique id to call data?
ethernet connect 46 pcs on my pc MySql server
etl Update more than 30,000 records row by row
uploading 300+MB files to MySQL db
euro sign load data infile: "Incorrect string value" with special chars
events Events: what if server is down?
Has anyone used "event" in mysql
excel Connecting to MySQL from Excel 2007
Import Excel in MySQL??
LOAD DATA
exchange partition Partition data backup and restore
exchange partition with table Is there a SWITCH equivalent in MySQL?
exclusion join which kind of join?
exit handle Transaction won't end
expand and contract Question about LIMIT
explain Slow select with sub queries
greatest-n-per-group performace for different data types
understanding towards Using where; Using temporary; Using filesort is right?
Help optimizing query/index
failover Switching to backup DB on error
Mysql 2 server replication setup with fail over
fast ingestion MySql table disappears at random after multiple TRUNCATE queries
fast random update Optimize multiple writes on the same row
federated How do I find out details of a Server link for Federated tables?
feed processing uploading 300+MB files to MySQL db
field Re: MYSQL Sorting IN by orignal order?
file priv CSV import with mysqlimport
file redirection Store dump from DB on Server A to Server B (File) and test restore on C
filesort Query Optimization - order by
always uses filesort even after adding indexes
Subquery with range uses filesort
filesystem databases and log files on separate hard drives
file_per_table All Innodb tables using seperate ibd, but ibdata1 still being modified?
TableSpace
filing cabinets random reads
find id hole How to create a solid sequence?
firewall Replication: Connecting Slave and Master
Error encountered on slave "Waiting to reconnect after a failed master event read"
first partition I searched table on one partiton, but MySQL scanning two partitons
first slave Start slave fails
Initial setup of replication with large tables
Setting up replication in a Windows Sever 2003 environment
Replication setup (for the first time)
fixed Estimate table size
Text(1024)
how table rows are stored at the file level
fixed vs dynamic MYSQL manual using MANY frequently changing Varchar(255)
Questions related to Row Format, Encoding, and performance
fk Foreign Key Error 121
Need help to improve innodb performance
another fool having problems with FK in InnoDB
flags Ноw better to store large number of flags?
best for true or false, Yes or No
float Bug in the floating point value
Is it possible to get MORE results by adding an AND clause to a SQL query?
Math function logarithm
float double decimal Comparison Between Floating Point Types
float unequal BINARY operator not working properly
for update table locking
foreach write trim into INSERT and SELECT Queries
foreign key Soln. for MySql 1005 (Can't create table)
dropping a foreign key constraint
Why use JOINS when have FK
ERROR 1005 (HY000): Can't create table 'Azienda.#sql-697_c9' (errno: 150)
Multiple references of a PK
Error 1005 Errno 150
#1005 - Can't create table (errno: 150)
foreign keys drop all constraints, then reinstate all constraints??? is there a way to do this??
Can't create table with Foreign Keys - errno:150??
found_rows Alternative to FOUND_ROWS()
fractional seconds [SOLVED] DATETIME does not keep fractional seconds (5.6.11)
fragmentation Table fragmentation and optimization
Performance increased after mysqldump restoration ?
does innodb table need 'optimize table'?
ft_min_word_len Working with short words in full text search
fulltext match against search won't match strings with a forward slash in them
accent sensitivity in fulltext search
Using FULLTEXT index with a boolean on the matched field?
Seeking advice on setup
Cascading deletes
Query not returning result in fulltext search boolean modeeven though records exist
functions good practice Connecting to MySQL on numerous pages
gap lock Minimize row locking for update statement
gaps scanning for data gaps in time series
general log timestamp No timestamps in general query log
geo Unused index, slow query
GEO Search with large table is very slow
grant One big DB or two not-too-big DBs? FKs across DBs are slower?
remote access and privilages
HOW DO CREATED USERS LOG ON MySQL CLI?
Re: Can't seem to create a new user account
How to change mysql username from "root" to "apps"
Make Table or Catalog Read Only
User password being modified as a result of grant statements?
MySQL users question
Why doesn't root get full privileges?
Revoke privileges from user issue!
Creating a restricted user account
grant host names connect as remote server
Can't connect with non-root user to created database
grant localhost creating database users
graphing Building Graphs with MySql data
group by problem with concat() distinct() min() and GROUP BY
Unsure about query... random column?
using GROUP_CONCAT
MySql 4.1 optimization search poor performance
distinct vs. group by
Noob query issue
group by trick Complex Select with Min/Max Syntax
Listing threads by newest posts?
How does group by algorithm works?
Subquery and JOIN's
limiting rows returned
max function
Help with minimum/group by
create function help
select max date in Inner Join
aggreate data
query returns unwanted duplicates
Require help to formulate a query.
Slow Query
Assistance required for query with subquery
Last or Max?
Unexpected Result when using MAX(id) and GROUP BY
group union [Query help] Table transformation
groupwise max max row from table
groupwise-max select max date in Inner Join
group_concat multiple rows into one line string with
Simple statement
group_concat. join Database efficiency question
guid SELECT took lengthy of time
How can I decide which partition type can I chose
GUID field
guid performance Deadlock Detection in InnoDB storage engine
ha MySQL HA 2 instances + iscsi shared data dir
replication or mirroring?
When do I start... partitioning?
Fail Over
hacker protection How do I assign unique id to call data?
handler HANDLER statement questions
Expected query time?
hash How should I make text column search faster?
having Simple statement
heartbeat for replication measuring slave lag without sysdate() - 4.1.13
hide password Running backup in cron without clear text pw
hierarchy Return the level and count of a closure table.
select max date in Inner Join
Building a widget/graph from mysql view
Unary many-to-many relationships
relationship query question
challenging problem -spliting different values within one field
high cpu Mysql using 95% of cpu
highwater Milli and Micro seconds in mysql
hints Intermittent slow performance
history MAX_ROWS on Partitions
Snapshot Table -- over the long run
Mysql cluster 7.1.5 can't use table partition!
New to design; how to optimize 3 column single table with high I/O?
holidays Query results from one table against a list created by another
horizontal partitioning RAM requirements- new server
hosts file Slow connection
How to troubleshoot slow response from MySQL
html why do I need to set encoding in the browser in order to see Arabic letters
html entities Storing Special Characters in Table
htmlentities Problem with fulltext search using encoded german umlauts (strange behaviour of "MATCH(column) AGAINST ('keyword' IN BOOLEAN MODE)")
htmlspecialchars Something like Server.HTMLEncode for MySQL
huge Which storage engine?
load data infile real-time data load
trillion records?
huge pages innodb memory usage vs swap
hugepages sanity check on innodb config
ibd How to restore innoDB tables without ibdata1 with innodb_file_per_table=1
TableSpace
BLOB storage file
ibd recovery InnoDB Transportable Tablespaces - Recovering Data from Stranded .ibd Files is a Thing of the Past
ibdata How do we resize ibdata file?
ibdata1 After creating tablespace .ibd, Mysql doesnot start
Switch to file_per_table using a slave
Different ibdata files for every database
mysqldump and import to de-fragment tables
data_free not empty
All Innodb tables using seperate ibd, but ibdata1 still being modified?
changing from 1 big file to file_per_table
TableSpace
ibdata1 contents ibdata1 and undo log
iblog Connection lost
Different ibdata files for every database
Innodb Log File Error
id Real-world DB schema
identifying relationship Please explain identifying/non-identifying relationships
ie caching MYSQL appears to not recache Selected table after Insert
ieee754 Sum of doubles giving incorrect value
image Image database in mySQL
image display problem from mysql database
retrieving a photo from mysql database
saving image in mysql
User-friendly approaches to displaying subtable data
image as blob Where are BLOBs useful?
image output Show images from database
imagecreate Show images from database
images Using images with php and sql
img src Show images from database
implode loop doesnt seem to run
import Need to Convert Date Time at Query runtime
impossible position Got fatal error 1236 from master when reading data from binary log
in PHPMYADMIN hangs on this query!.HELP!!!!
Efficient string comparison to a group of values
Why isn't an index being used here (nested query)
Optimizer executes inperformant subquery first
in select Using NOT IN
Optimizing a query so that the smaller table is handled first
in-list PHP filesize and storing a big WHERE clause in a variable
incompatibilities Moving Mysql to a new server
Re: max(DateField)+C <> max(DateField+C)
index Re: Large range query stops using indexes
Slow query on very large table
index selection
How does index perform with LIKE?
how to solve this complex query
making a row unique
GEO Search with large table is very slow
how to optimize this query
Order by using filesort on where
Advice on redundant indexing
Help with optimize SELECT
does unique index do more than just being a constraint?
Preferable Index Length
Mysql does not use index, even if example is trivial?
DATETIME vs. INT(11)?
Statistics used by optimizer.
Concat Occasionally Drops a Character or Two
Query is so slow
Index not being used
Is index needed or not?
Rebuild Indexes Online after Insert/Update
combined index ignored
Multi column indexing question
index performance on "limit" condition
Problems with query not using expeced indexes
Attempt to split big table into smaller one made query slower
Primary key - link to data ?
Need help on indexing
Statistics
Improving Slow Query
Indexes: how many, how much?
Lock wait timeout exceeded; try restarting transaction
InnoDB to MyISAM
Query with > 500000 entities in in where clause crashes server
tables with 3,500,000 rows, indexed but still v slow
multicolumn index & forcing index to avoid filesort
COUNT(*) very slowly in large InnoDB table
performance issue on order by index
Estimating Index Size on Innodb Tables
Join Statement with math operation
Huge row size compared to MyIsam
CREATE TABLE ignores DATA DIRECTORY option
Need Database Structure Help
Size of INDEX_LENGTH is higher than DATA_LENGTH !
Index recomendations
Slow query with order by and limit
11 millions records : more than 30 seconds to retrieve simple request
Table marked as crashed and last (automatic?) repair failed
Partition on day of year
Stop using filesort
physical bytes
Best primary key or index
Problem with a query performance
indexing
Help optimizing query/index
Creating an Index
Does LIMIT 1 without ORDER BY ID bring the record with minimum ID?
Understanding MySql optimization of Queries
Optimize Inner Join With WHERE BETWEEN dates
Slow insert rate in mysql innodb
Question about indexes
is good have single index an composite index on same field
Function and indexes
index creation checking status of CREATE INDEX
index design MySQL not using indexes
Backup and trimming data idea
index details how index grows in size
index examples Slow query. Why is it slow?
index join ideal indexing for inner join, rowcount of 1
index not used Indexing is done for single table, but its not working for most of the queries.
index order Optimization of where clause
index size I've got two Tables and wonder why a table with less data can have a bigger keysize?
index-10-30 MySQL 5.1.49 - Optimal settings for memory usage
indexing Looking for understanding of optimizing queries
Issues with possible duplicate indices on table
MYISAM INDEX KEY Question
information schema SHOW VARIABLES: which table holds my.cnf startup varibles?
Wrong info from Information_schema
information_schema creating data dictionary
Procedure is not working
init_connect Encoding problem
injection Unique Constraint Using My Own Definition of "Equals"
Db access/privileges philosophy
inner join Optimizing query
innodb evaluating table locking
ANALYZE TABLE not working correctly
slow queries and high % of wait I/O
Reduce Index space
Alternative to FOUND_ROWS()
mysql very slow after million insert/delete
AUTOINCREMENT & ROLLBACK
Negative consequences of converting to InnoDB?
Insert into table on duplicate key update - performance issue
COUNT(*) very slowly in large InnoDB table
Replication lag when no primary key on InnoDB
Huge row size compared to MyIsam
New to design; how to optimize 3 column single table with high I/O?
Does LIMIT 1 without ORDER BY ID bring the record with minimum ID?
innodb analyze Different Servers Using Different Index for Same Query on Same Data
innodb blocks Varchar does it cause data file to continously grow
innodb corruption Table corruption
innodb count(*) Slow access to large tables
innodb fragmentation Is my data fragmented?
fragmentation in innodb index
innodb free Can I automatically reuse the free space of a table that in the InnoDB
innodb free space data_free not empty
InnoDB File Size
fragmentation in innodb index
innodb fulltext MySQL 5.6: InnoDB Full Text Search (FTS)
innodb index problem about second index on innodb
innodb internals JemeryCole/Twitter: Deep Dive into InnoDB Internals
innodb io buffer pool read/write?
innodb log files Setting innodb_log_file_size disables the innodb engine
innodb pk Need help to improve innodb performance
innodb primary key Primary key for referee table.
innodb random dives can mysql use 2 different execution plans for the same query ?
innodb row size Row size
innodb semaphore contention quantifying activity at the buffer pool?
innodb settings Innodb_buffer_pool_pages_free = 0
innodb size Automatic Extension Question
innodb transportable tablespac InnoDB Transportable Tablespaces - Recovering Data from Stranded .ibd Files is a Thing of the Past
innodb vs myisam InnoDB to MyISAM Disadvantages?
Innodb v/s Myisam
innodb_buffer_pool_size Max size of innodb_buffer_pool_size
innodb_file_per_table poor performance on good hardware
Can we have different tablespace for indexing in innodb storage engine?
How to create TableSpace
Separate databases in separate files
How to stop a database growing in size on the disk
innodb_flush_log_at_trx_commit limitation on request per second
Very slow query for no apparent reason
MySQL InnoDB performance tuning
innodb_locks_unsafe_for_binlog Getting "Lock wait timeout exceeded;" when using "for update"
MySQL 5.6.12 and many deadlock
innodb_log_file_size Switch off InnoDB logging - Possible?
Reset Root Password causing ib_logfile issues
values in my.ini for 2GB RAM
Unexplained drop in performance?
innodb_log_file_size
Correctly setting mysql options for a huge DB with intense trafic
Power failure and innodb
innodb_log_file_size formula how to calculate innodb log file size
innodb_max_purge_lag mysql very slow after million insert/delete
innodb_os_log_written MySQL Server locks up daily
innodb_stats_sample_pages More Stable Query Execution Times by Improving InnoDB Statistics
innodb_table_monitor Foreign Key Error 121
ins Updating multiple rows with an array using PHP with mySQLi
insert Slow Inserts
Inserting 5000 samples per sec in real time
insert on duplicate key Problem of indexing Country, State , City
insertion speed Need mysql Configuration Parameters that affects Insertion rate
inserts Need help to improve innodb performance
Insert into table on duplicate key update - performance issue
install on windows Solution: Cygwin and DBD::mysql
installing php Apache 2.2.22 with PHP 5.2.17 don't connect to MySQL
interactive_timeout Close conections
into outfile Export Recordset query to a file nightly? Ubuntu and MySQL
io big random-access I/O
ip What data type should I use and what storage engine?
Help with the best table layout for message board
Slow query
ip range Optimize IP Range Join
optimize IP range join: postgresql is 496 times faster
update big table cause an excution time out
How can I optimize this query?
Keys ignored for larger tables!?
iterative update Updating 100 million record tables
java time Storing Java Timestamp (long) in database as BIGINT?
join Some general questions
JOIN table USING vd JOIN table ON table_field=another_table_field
PHPMYADMIN hangs on this query!.HELP!!!!
trouble figuring out joins, any gurus out there?
INNO DB performance problems with temporary tables
nested select
tables, joins or not, to script or not
After upgrade from 4.1.22 to 5.1.44 query not working
JOIN, and LEFT OUTER JOIN: I don't get it
Join Syntax Confusion
Difference between two SQL queries
join 101 Need help with a more difficult query
join opt explained MySQL 5.1.31 -- Same query scans widely different # of rows
join order can I use two join in a single query ?
join vs subquery Faster SQL - newbie needs help
"Optimizing sub queries with joins"
join vs union Left Join between two large tables too slow!!
joins Problem with SQL query :(
json User defined fields in a schema
json for eav What's the worst that can happen with below database design? Immediately or in the future?
key value linked data
Query Optimization
Create tables: Shall i use one table or different tables in order to store data?
How best to storing User Profile data
Help collating multiple rows from multiple tables into a single row
Large number of columns causing - Unknown Error
table/query help
How to speed up Query with WHERE AND/OR, with Subqueries using IN
Data model metadata design and data driven joins
key-value User defined fields in a schema
key_buffer Processor at 99.9%, memory at 5%. Configuration help?
Queries slow down daily, optimizing helps -> why?
Key_Buffer_Size
large multiple table update taking a very long time, help!
mysql max_connections
key_buffer_size version Help make my big new server fast
key_len Multi-Column indexes
key_reads Memory settings for server with 4GB RAM
What happens if the size of an index file exceeds physical RAM?
kill how to stop it
kv Opinions on this schema please =)
kv table “CACHE INDEX” and “LOAD INDEX INTO CACHE”
Having an argument about table design
language recommendation MySQL / WebFront End / Best Language to support?
last_inserted_id How do I combine 3 queries into one
last_insert_id Looking up a value in a 'subtable' and inserting it if it doesn't exist
Update query problems
Transaction deadlock with many threads
Select and update at the same time (with selected value)?
Problem of indexing Country, State , City
lat lng Slow select on table with 1.8 million rows (filtering on lng/lat)
How to improve query performance in expression related order by?
lat-lng select query in from clause creates problem
latitude and longitude Optimised way to search over 2 milllion poi data in mysql
latitude/longitude query not using index
layer mysql user access level
When do I start... partitioning?
lead and lag Oracle Analytical Functions
leaderboard RANK() emulator?
leap seconds PHP and MySQL time not same
lecture Poor Performance with tables over 1Million entries
left join Help w/ data modeling, 1 to 1, 1 to none? hack?
need help with cross referenced tables
Help with query with conditions
Help with Join Query
need help! query to get absentees list
left off 30M rows - is dynamic sorting and selecting even possible?
How do deletes and updates affect fetching of rows?
Innodb PK in secondary index
next/previous on a date select query
left_off should i go with myisam or innodb?
licensing MYSQL Community vs entreprise
like is good have single index an composite index on same field
like suffix How to fast search in 3 millions record?
limit MySql 4.1 optimization search poor performance
Using LIMIT in a SELECT statement which does a JOIN
index performance on "limit" condition
Index not working as I expect
limit helps/hurts optimization MySQL Explain rows limit
limits Storage capacity
Max quantity users in MySQL
Data object standards
Maximum Constraints Per Table
ln -s How to Install MYSQL that comes with SLES 10 on a SAN mount point instead
load Testing the updated database whether it is properly updated or not
load balancer Master-Master Active-Passive loadbalancing with ultramonkey
load data Append with LOAD DATA INFILE
need to upload .txt to SQL table.
Load Infile - Not able to import microsecond level datetime from CSV
CSV import with mysqlimport
loading data problem
Proper syntax of LOAD DATA INFILE
load data expression Mass Import Innodb
load data local load data errror ONLY on remote server
load data paradigms Importing Data from an XML Document into a MySQL Table
load data set variable Null values are replaced with zeros in infile.
load data variables Is it possible to use variables and string functions with LOAD DATA LOCAL INFILE?
localhost creating connection to "Server Administrator"
locate Comparing strings
locking Minimize row locking for update statement
locks Solving table locking issues
Help with locks
Are queries queued?
lock block deadlocks
log files Log files filling up
log sequence Index not used in certain DELETE-queries?
log-slow-slave-statements Replication server is running behind
login Mysql and CentOS 5.2
Need Help - Server was hacked
MySQL on Ubuntu mess...pls. help
login access Access
logs mysqldump for BLOB?, InnoDB log files?
log_warnings Prevent logging for unsafe statements
long running transaction Query id on SHOW INNODB STATUS
longblob MySQL kills itself when cannot allocate X bytes
look for impact of havig both concurrent_insert=2 and low_priority_updates=1 together?
loop thru Cursor usage with Prepared Statements
Select query too slow from merge table of 1 billion records
lots of tables MySQL 4.1 to 5.1 large scale upgrade
lower Using DECODE with SELECT and LIKE
lower_case_table_names Change DB to case-insensitive = problems
lvm Replication setup (for the first time)
maatkit How to know if a slave is identical to his master ?
mac install Problems creating my.cnf / options file
make commalist while loop - how to remove last comma
many tables tables per company - why not
many-to-many Need help on designing simple db
Problem creating table with 2 primary keys
Simple many to many query...
many:many Bulk data question
1 to many and many to many help
Learning Management System MySql Database design
Unary many-to-many relationships
many:many relationship best practices in relationship
mapping Basic conception for database
mapping table Tables optimization for messages feature
Inverse Lookup in Key-Value Storage: avoid disk seeks
INSERT IGNORE ... SELECT performance question
master-master How best to support global website?
max InnoDB to MyISAM
max-allowed-packet-size ERROR 1153 (08S01) at line 356771902 in file: 'mysqlmulti-bins.sql': Got a packet bigger than 'max_allowed_packet' bytes
maxclients To many sleeping connections
max_allowed_packet Maximum number of records the "SELECT IN" operation can handle!
MySQL server has gone away
How long does a query take?
max_allowed_packet and its impact on backup (and replication)
Not enough memory to allocate insert buffer of size 1073741824
max_connections Debugging too many connections
How to get MySQL concurrent query nos.
Does a too many connections error always really mean it?
Question on max_connections
Both master and slave stop accepting connections
max_connection
Can the use of Ephemeral ports be disabled?
max_heap_table_size Real weird slow down with select count(distinct x) and high max_heap_table_size
max_join_size "SHOW VARIABLES" and "mysqladmin variables" show different settings
max_open_files Error 23, 1016: Partition with MyISAM
max_rows Will increaseing table size affect current data?
MAX_ROWS
max_updates ERROR 1226 (42000) at line 1129: User 'root' has exceeded the 'max_updates' resource (current value: 100)
md5 Fastest way to check for an image in a table
How should I make text column search faster?
SHA-256 which data type is the best?
meb MySQL Enterprise Backup Remotely
median How do I get the median instead of average?
meet in the middle Multiple Databases - Search and retrieve.
meet me halfway Ignoring certain characters with SELECT query
I'm looking for the best way to join two tables based on the matching of the words in a varchar field in one table against a varchar field on another table
memory InnoDB log group capacity error
Anybody met this errors :Out of memory (Needed 16777224 bytes) ?
Slow Updates on Memory table - (detailed)
Optimising max_heap_table_size & tmp_table_size
how to estimate the real mysql memory consumption?
mha Disaster Recovery with master-master replication
Setting up Circular replication in existing replication infrastructure
middle Another Complex Query
regexp challenger
milliseconds Date/Time Query
Milli and Micro seconds in mysql
mixed replication Replicating from innodb server to myisam server
mongodb Comparison b/w mongodb and mysql
more_results stored procedure with cursor only returning one row in PHP -- works in MySQL client
move datadir Not able to move database to mounted LUN in linux
moving average Moving average
mrr MySQL 5.6 update doubled IOs
mssql DataMigration from Sqlserver to MYSQL (Experts help need!)
mssql conversion convert mssql function to mysql function
mssql functions Converting Functions from MSSQL to MYSQL
mssql to mysql Migrate a MS SQL server database to MySQL
mtype MySQL 5.6.21 signal 11 crashing instantaneously after START SLAVE
multi-master Multimaster replication set up with a single slave
multiple disks Chaning database dir to another hard drive
multiple key_buffers Anyway to identify the special key_buffer_size
multi_query stored procedure with cursor only returning one row in PHP -- works in MySQL client
mutex What's the difference between concepts--latch and mutex?
mutexes MySQL + 2 x Intel Xeon (6 cores) performance problem
Why does MySQL's performance decrease when queries are executed in parallel?
my.cnf Slave is not updating some tables .....
my.ini location Error 10061: connect to MySQL server failed
my.ini my.cnf How do I find what configuration files were loaded
myd BLOB storage file
myisam random reads
is 16 gb ram enough for handing mysql database of size 100 gb having myisam as storage engine ?
myisam advantages Transactional vs. NonTranscational For The Layman?
myisam auto_increment How MySQL MYISAM manage the auto_increment column
myisam indexes Significance of Primary Keys
myisam pointer size Table full message when data is just over 16MB
myisam vs innodb should i go with myisam or innodb?
Database effeciency
HELP! making choises on Performance - Storage engine - Caching
New to InnoDB (want to convert from MyISAM)
myisam-innodb Error Duplicate entry - Master-Slave replication
myisam_data_pointer_size myisam_data_pointer_size
myisam_max_sort_file_size enable keys, force sort, not keycache
myisam_sort_buffer_size myisam_sort_buffer_size
Repair Will Not Use Filesort
"Alter table enable keys" randomly using "Repair with keycache"
mysql history Why does MySQL's performance decrease when queries are executed in parallel?
mysql server has gone away Running Large scripts from command line
mysqldump Aborting Optimize Table for Innodb
How To bakcup Databse per table ?
Best Prctice export from MySQL 5.1 to 4.1
what should i do when backup ?
Partition-wise mysqldump backup script at MySQL Forge
MySQL Backups - Innodb
backup database
stored procedures and functions
moving mysql database
mysqldumpslow Problematic Query identification at the time of load on server
mysql_proxy MySQL Proxy - Production Worthy?
mysql_real_escape_string Adding a filename to a MySql database
my_use_result Memory Allocation error
name Order by using filesort on where
navicat Import and export flat files containing backslashes
netstat Replication: Connecting Slave and Master
network Switching to backup DB on error
net_buffer_length max_allowed_packet and its impact on backup (and replication)
new slave Adding slaves to replication environment
new slave from old 1 Master -> Many slaves, need to update dump file
new thread 1135 Can't create a new thread (errno 11)...
newbie building tables
nmap Replication: Connecting Slave and Master
nondeterministic replication A qq reg SBL with current_timestamp()
nor indexing on every column?
normalization Design of tables
ERD Design HELP!
Is my database normalized?
How do I count the number of rows with certain data
select * where value>1
Newbie Normalization Question
Insert keys from 1 table into 2 others.
Rock/paper/scissors design
normalize Time series database design
finding it hard to setup the relationships
Performing multiple updates and selects
Standard way to store user information
Database Normalization: Always the best thing to do?
JOIN vs Denormalize table vs Vertical partition
not using index Problem with a query performance
null after moving database problems with NULL value
Using null to mean all or any
nulls NULL but TRUE
numa Poor performance of MySQL 5.5
numbering rows SubQuery and result
o'brian Mysql query produces different results for different users
odbc Configure Database
How to open MySql?
offline backup Offline Backup
omg UPDATE a field SEVERAL times in 1 UPDATE
on duplicate Deadlock occuring since setting a unique index.
on duplicate key How do I combine 3 queries into one
one-to-many Subtypes can they be related
oo PHP OO mysqli query problem
open file limit max_open_files error
optimize does innodb table need 'optimize table'?
optimize innodb Optimizer for innodb does not reduce "data_free"
optimize table Optimize table statement
Optimize table and fragmentation
Execute table optimization concurrently
optimizer Optimize Inner Join With WHERE BETWEEN dates
optimizer_search_depth Query Performance Problem
select with join of 25 tables crashes mysql database
or Extreme high load and low throughput using MySQL & Hybris on an HP DL380G5, quad-core Intel, 4GB RAM
Help optimize query
index usage dependent on in(group) content
Poor performance with an "OR"
or to union Long execution time despite LIMIT 3
WHERE OR performance issue
oracle Bitmap Index
order by unique ID field, getting next and previous existing ID from table
Re: MYSQL Sorting IN by orignal order?
distinct vs. group by
Query Optimization - order by
order by field Order by my order. How to ?
How to keep order of values inside IN() operator
showing records in order given by in clause
order by list IN order
order by rand Slow MySQL Queries
org chart Building a widget/graph from mysql view
os Table fragmentation and optimization
os limit Error: ORDER BY clause
MySQL fails to start
over-normalized Big problems on optimizing query
pager Index not used in certain DELETE-queries?
pagination MySQL Performance Tuning on my server
Query performance on database with joins
Slow search query
Query performance question (using index slows down?)
Alternative to FOUND_ROWS()
Very Slow Simple Query
break mysql query? Is this possible in my sql
Query that returns indexed fields involves FILESORT, why?
join in union
Efficient MySQL for pagination of large amounts of data on website
Showing recordsets from tables with one (main table) to many (secondary table) relationship
Use of memory table vs temporary table question
Heavy task on mysql by AJAX Pagination?
Jet Profiler says I'm slow....
pagination - precalc Handling Large Datasets
pairs Query To Find the Number of Self-Joins?
paragraph Retaining paragraphs in text data type
parallel Performance LONGTEXT / LONGBINARY
large multiple table update taking a very long time, help!
parallelism Intra-Query Parallelism in MySQL Server
partition MAX_ROWS on Partitions
How to partition my table
Table partitioning
How to create partition on existing table?
Partitioning with range(to_days) issue
Partition-wise mysqldump backup script at MySQL Forge
Improving Slow Query
How to handle secondary keys in partitioning?
Exceptions with Partition Pruning
How can I decide which partition type can I chose
Open tables with Partitioning
MySQL performance help
partition by range on decimal type
count rows in a partition
How to stop a database growing in size on the disk
Simple query seems to be ignoring date index
partition add drop Using MySQL Partitioning Instead of MERGE Tables
partition auto_increment Partitioning by date, and maintaining uniqueness
partition by day Problem with granularity choosen
Add new partition for Range by date
partition by list Fortnight partitions
partition discard Backup one of the sections in innodb table
partition mapping table How to partition that table?
partition null Partition Pruning
partition priority queue KEY vs RANGE partitioning
partition suggestions Move from unpartitioned database to partitioned database
partition use cases When partition a table
password Help on MySQL 4.1 & PHP 4.3.11
creating connection to "Server Administrator"
any cheat-sheet style documents?
What do you do with the database user passwords?
pdf MySQL blob performance
pem SSL error: Unable to get certificate from '/etc/mysql/newcerts/client-cert.pem'
percent improvement What hardware factors influence MySQL query execution time
percentile Why I can't insert more than 100,000 rows in a script?(mysql+php)
can i quickly do a 95th percentile in mysql
Calculation of a '95th percentile'
Counting occurences of data falling betwen a series of limits (buckets)
perf slow queries and high % of wait I/O
random reads
Statement/row questions
Any way to optimize join to find rows without conditional foreign rows?
Very slow DELETE, UPDATE, INSERT on a new server
performance CentOs or Oracle Linux?
performance_schema MySQL Performance Schema: Overview
MySQL 5.6 update doubled IOs
permissions Replication problem
persistent innodb statistics timestamp, datetime as default value as current_timestamp [PARTITION]
petabyte How to scale MySQL Cluster to support PB storage
phone numbers When to use separate tables.
phones printing fetched values
Creating a variable variable name
php Storing Special Characters in Table
php build where mutiple field query
php escaping Mysql query produces different results for different users
php file upload How insert data in table using a .txt file
php flow Creating report filter by name in one table
php install Your PHP server doesn't have the MySQL module loaded or you can't use the mysql_(p)connect functions
Error when trying to configure PHP to work with MySQL
php log_errors Pasted text not saving
php mysql_fetch_array PHP access not working right
phpmyadmin cannot change character set
physical copy physical export
piping Store dump from DB on Server A to Server B (File) and test restore on C
pivot Need help with a Query....cross tab format
Pivot Table Rows into Columns stored procedure
insert 0 when combing tables?
Cross-table in stored procedure
Pivot tables
plesk ubuntu Always get "Access denied for user 'root'@'localhost'" after installing
plugin Plugin 'InnoDB' init function returned error.
upgrading to innodb plugin
How to create TableSpace
polish Unproper order of sorting in utf8. Collation?
portuguese Using accentuation or other special characters and printing with php.
ppm perl script hangs on query with where clause
precision Math function logarithm
prefix index usage dependent on in(group) content
Slow Query for Alphabetically Adjacent Terms
prefix index Very slow sort on Order By for MySQL query.
preload cache Preloading Index - LOAD INDEX INTO CACHE problem
prepare prepared statements for multiple queries
prev value Getting data from previous row
primary key Primary Index
Replication lag when no primary key on InnoDB
Question about indexes
table with multiple primary key
privileges Db access/privileges philosophy
procedure Procedure is not working
progress bar is automatically monitoring progress impossible?
prune Noob question - simplist way to store last 4 viewed products?
pt-query-digest Problematic Query identification at the time of load on server
pt-table-checksum Comparing large slaves to master
pt-table-sync Comparing large slaves to master
pta Tracking past group memberships of multiple groups
pwd security Designing a forum - general design logic question
qc Linking to a LUT more than once
qc too big Randomly slow Insert / Update on small table
qps Help make my big new server fast
Database Pool Size
query cache Queries slow down daily, optimizing helps -> why?
Why is my entire database getting locked for a slow select query?
Query cache was never filled up
Understanding the Query Cache and the Innodb_buffer_pool???
A fast (>0.01s) query sometimes slow (>2s)
Query Cache Causing High CPU Load
Poor performance of MySQL 5.5
query cache no MySQL 5.5 and Query Cache
queue row-level lock that prevents SELECT?
queuing FOR UPDATE and LOCK IN SHARE MODE
quotes delete query doesnt work with php
Looking for Rule on quoting
quoting MySQL Output Help
raid databases and log files on separate hard drives
CREATE TABLE ignores DATA DIRECTORY option
InnoDB and separated disks
5.1 to 5.5 upgrade causes significant write slowdown (MyISAM + indexes)
raid controller Inserts very slow
ram MySQL eats all of RAM memory
is 16 gb ram enough for handing mysql database of size 100 gb having myisam as storage engine ?
rand evaluating table locking
small DB, big problems
select limit records from 600000 records
rand() to randomize rows only once daily
random Horrible performance on BLOB's when using WHERE or ORDER BY
random sorting - what is the quickest method?
random dives Analyze question
random fetch Very Large Non-Dynamic Table for Lookups
random id best way to generate a random unique id
random index Fact Table Partition Design
range Select * from MyISAM table returns PK order / filesort order
Simple Query -- Needs to be Mind Numbingly Fast!
ranges I want to write a user-defined Aggregate Function
What Method is Best
rank RANK() emulator?
your ranked out #x of X accounts?
Get row of a specific result
rank order sp vs query window
rbr Row based Replication: Deadlock is not rolled back
rdf About performance for Database of millions of records
linked data
read committed MySQL Backups - Innodb
read-write separation Forwarding writes to master
recovery Restore InnoDB schema from partial backup
redo logs Power failure and innodb
redo transaction fix "Deadlock found when trying to get lock; try restarting transaction"
ref range Query using "ref" instead of "range" access
regexp REGEXP() Question
RegExp Question
how to find particular string from text column
mysql regexp issue range
Pass Numeric Values From Form To Set Data Lenght +...
regression Mysql 5.1 to 5.5.1.18 Upgrade Poor Performance
relay how to setup master, primary slave master and slaves
relay log PURGE BIN LOGS FILES NOT WORKS
remote connecting to Mysql server running on a different machine
rename Bulk updates on live database
insert or load ? best practices and performance
rename table Importing a database dump created with --single-transaction does not result in single-transaction import of the file
why my db don't use index?
reorganize partition help making event for auto delete of partitions
repeatable read Uncommitted rows are updated by a second transaction
repeatable-read MySQL server configuration for a 8 cpu+20gb RAM server
repl mysql replication issue (Handling write load on slaves)?
replace Character encodings issues with php, mysql, apache
replication master-slave replication good solution?
Upgrade from 5.0 to 5.1
Replication multiple database
Can't restart slave - Could not initialize master info structure
Replication problem
Need advice to Setup replication server (INNODB)
replication or mirroring?
update slave after failover
Error Duplicate entry - Master-Slave replication
replication bug MySQL 5.6.21 signal 11 crashing instantaneously after START SLAVE
replication checklist setup mysql replication on CentOS error
replication designs conflict resolution
replication lag Slave is lagging from master
Master - slave connection
replication sequence of events is it possible replicate with mysql5..5
reset root password Setting up root password
unable to create database even as root user
resignal Stored procedure, stored function and signals
resize Different ibdata files for every database
resize iblog Caonot change innodb_data_file_path
result caching Memory Allocation error
resultset Question: Technical Background Of The Result_Set
reverse How to fast search in 3 millions record?
reverse lookup Slow Connection
revoke Make Table or Catalog Read Only
Revoke privileges from user issue!
revoke proxy Create new user by using MySQL CREATE USER statement
rollback Transaction won't end
rolling window average No Window Fns in MySQL?
root Resetting the Root Password on Windows
Need Help - Server was hacked
Debugging too many connections
creating connection to "Server Administrator"
any cheat-sheet style documents?
MySQL users question
Why doesn't root get full privileges?
rot Help optimizing query/index
roundtrips Alternate for Varrays in Oracle
row size exact row size of InnoDB table
blob to mediumblob or largeblob
rowid internal rowId
safe-updates "SHOW VARIABLES" and "mysqladmin variables" show different settings
san What is the story of NAS and SAN file systems for Database?
How to Install MYSQL that comes with SLES 10 on a SAN mount point instead
scaling Skyblog, Friendster, twitter, yahoo mail..... how to design database for huge no. of users and rows
design distributed database
word index - is there a better solution?
scaling via slaves Three Node Replication (US West, US East and Europe)
schema select query not using indexes
Where to find a tool for differences between two database structures
Up to 1 million rows Performance + Design Help
I have queries that sporadically take a very long time
scrubbing Tools for Scrubbing Entire Mysql Database
search Searching with accented words
search form Problem with search when add BETWEEN to query
searching SQL instructions enclosed in "/*! ... */"
seconds_behind_master "Seconds behind master"-Value jumping
secrets Long query locking up MySQL Server
security Replciation Security
Actual Newbie Question with mysql connect
Changing Plain Text Passwords to Hashed Passwords
Database Encryption
Connecting as a User
Building Memory Table from AES Encrypted Physical Table
What do you do with the database user passwords?
select Rewrite Full Outer Join into Subquery
select * optimised way
self join trick grouping query results in their order
selinux Moved datadir and now get: ERROR! The server quit without updating PID file
startup mysql as service on redhat enterprise linux 6.4
semanage startup mysql as service on redhat enterprise linux 6.4
sequence A sequence solution for those that want it
Unique columns over two tables
Record Position in Ordered Selection
Last/highest ID?
Simulating sequences
server_id How server id is communicated?
session Max_used_connections
set search comma separated db column
PREG_Match?
set names Re: Korean characters displaying as ???
load data character set question
import utf8 to latin
Data is being in non readable format.
Problem with Accented characters while migrating SQL server to MySql server
set names utf8 Problems with Spanish characters
Encoding problem
sets Help with query...
setup slave New to MySQL Replication
sharding performance: sharding and replication ideal?
How to scale MySQL Cluster to support PB storage
Database Sharding at Netlog, with MySQL and PHP
Skyblog, Friendster, twitter, yahoo mail..... how to design database for huge no. of users and rows
Are there any pitfalls with having multiple MySQL databases on 1 server node?
When do I start... partitioning?
sharding steps
How to enable index fast in MyISAM table
shared memory mode How to connect with Workbench to server in shared-memory mode ?
sharp s Problem inserting german and french characters
utf8_general_ci (MySQL 5.0.x vs. 5.1.36)
show master status how to setup master, primary slave master and slaves
show slave status slave stuck
sig alrm SIGALRM blocked by MySQL
signal example Date check on insert.
simple index Query Tuning techniques
skip grant tables unable to create database even as root user
skip-name-resolve [SOLVED] Can't connect to remote server
skip-name-resolve and access issues
slam Help collating multiple rows from multiple tables into a single row
slave PURGE BIN LOGS FILES NOT WORKS
slave initialization Quick replication questions
slave invalid position Exec_Master_Log_Pos doesn't move (invalid position?)
slaves Slave to master replication
slave_open_temp_tables Replication, Stored Procedures & Temporary Tables
sleep To many sleeping connections
sliding segment Adding Segments in Table
slow select query not using indexes
my system usage hits 100% at every 6 hours.
Slow search query
use index on a view
350+ million rows -- is this as fast as it can get? (too slow at the moment!)
Slow Mysql optimizer
slower I have queries that sporadically take a very long time
slowlog MySQL using 80-90% of CPU
CPU usage spikes to 100% every week or so
Query Tuning techniques
MySQL performance on a HP DL385G7
snapshot MySQL & SAN
MySQL Replication
Replicating a big db
Mysql SAN Related Scenarios
Faster dump using mysqldump
snodgrass Time series database design
social search Theoretical Database Table Structure
socket MySQL Socket Error
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
sort-union Queries using WHERE IN and ORDER BY LIMIT
sort_buffer_size Optimizing MySQL filesort with small limit.
sp create function help
sp backup How to backup Stored Procedures
sp prepare limit ERROR 1064 , in stored procedure
space Aborting Optimize Table for Innodb
speed up inserts No Limits - Memory Engine
speedup I need Optimizaton of a Query - DISTINCT
sql injection Two usefull functions(XSS/SQL injection).
Multi user issue
SQL Injection
$_POST Help :
Text box security
Multiple databases
Assistance with securing input
Numbers Vs. Characters in MySQL Database
sqlexception Transaction won't end
sqlite Convert MySQL to SQLite
sqlserver Switching from Sql Server
sql_calc_found_rows full table scan for limit??
Query that returns indexed fields involves FILESORT, why?
resultset rows performance
sql_mode Load data infile not working
sql_slave_skip_counter Replication Errors on Slave DB
ssl SSL error: Unable to get certificate from '/etc/mysql/newcerts/client-cert.pem'
Failed to Setup SSL warning
SSL connection works but SSL Replication does not
ssn field types syntax
start end How MySQL Uses Indexes
start_time Index on datetime type
start_time end_time Query not using index
stateless html When to open/close the MySQLConnector
stateless http How many users on one connection?
stddev What is the SQL equvalance to VARIANCE
stopwords FULLTEXT search failing
stored procedure MySQL Stored procedure Tutorial
stored procedure with cursor only returning one row in PHP -- works in MySQL client
strict Testing the updated database whether it is properly updated or not
Upgraded MySQL - Lot's of Similar Errors
string as number Problem with MySQL SELECT
stripe Can a Mysql MyISAM or InnoDB table benefit from the STRIPE feature of disk device?
Can a Mysql MyISAM or a InnoDB table benefit from a set of multi-thread and multi-disk I/O device?
str_to_date Need to Convert Date Time at Query runtime
Datetime conversion fails
stumbling Why INSERT performance has not increase in sub-table?
subqueries Why are no indexes used in this case?
subquery Please help with slow easy query
Get statistics using self joins
Performance of WHERE EXISTS query
100% cpu usage on single cpu core
nested select
tables, joins or not, to script or not
Partition on day of year
slow query in Inndb
Rewrite Full Outer Join into Subquery
subquery - 5.6 optimization Dead query
subquery can help Optimizing it even more
Simple JOIN is extremely slow.
Strategy needed for picking random rows
subquery to join How kan I optimize this Code?
sum data_length MySQL 5.5.31 cripplingly slow
summary Design approach for summary table by 3 items
compressing tables
Counters
Database Design for huge set of data
InnoDB CPU Spikes
Very long query doubt... (Monster query...)
Slow JOIN to convert IP to Country Code
Best way to store/access large amounts of data?
should i go with myisam or innodb?
Large table designissue
Partitioning with range(to_days) issue
Multiple complex queries
UNIX_TIMESTAMP Duplicate key
views, unions and different dbs
Slow 'sending data' phase on mySQL query, for simple query
Thinking about sorting articles..
Index performance
Storing a large, dense tensor (35gb scientific data) -- is mysql appropriate?
Large Table Architecture
summary table Bitmap Index
To store or calculate on the spot?
summary tables Solving table locking issues
Which storage engine?
Killed by joins. 1 minute selects in Access, 15 minutes in mySQL
GROUP causing Using Temporary Using Filesort
Partitioning or Not Partitioning?
super freaking select with join of 25 tables crashes mysql database
surrogate key Primary key for referee table.
swap Regarding use of swap memory for MySQL.
Basic Standards of Mysql server variable setting
Strange disk usage in mysql datadir (partition)
swap tables MySql table disappears at random after multiple TRUNCATE queries
swapping Very Slow Simple Query
symbol Simple query seems to be ignoring date index
symlink Different data directories for different databases?
sync_binlog Got fatal error 1236 from master when reading data from binary log
Got Fatal Error 1236 From Master Reading Data from binary log possibility to loose data/?
crash recovery of sync_binlog=1 and innodb_flush_log_at_trx_commit=2
table design DB Design - Users Table
table lock SELECT queries Locking Problems
table name case Case Sensitivity for View Names
table name casefolding mysql and xampp
table of ints select dates in a month that fall on a given day of the week
table scan Select * from MyISAM table returns PK order / filesort order
field equal to OR between 2 fields?
full table scan for limit??
Optimising a GROUP BY and ORDER BY in a joined query
Question on bad execution plan
tablespace How to create TableSpace
tablespaces Importing Data with Single .ibd file
table_cache Optimizing table_cache - Open files?
table_open_cache Open tables with Partitioning
teaching Teaching mysql to teens
tee importing Text to MySQL
temp table Outfile Using too much disk space
temporal MySQL 5.6.21 signal 11 crashing instantaneously after START SLAVE
temporary table Storage engine used by temporary tables
text InnoDB log group capacity error
TINY TEXT vs Varchar(240) and TEXT vs Varchar(300-500)
large multiple table update taking a very long time, help!
thread stack overrun Writing my first Stored Procedure
What is wrong with my Stored Procedure?
timestamp Different timestamps for time of creation and time of update
how to convert timestamp value to string in MySql
Date - unix_timestamp
timestamp default Timestamp fields
timestamp microseconds convert seconds to minuts
timestamp vs datetime DATETIME vs. INT(11)?
#1452 - Cannot add or update a child row: a foreign key constraint fails?
timestamp(14) Error: Too big precision 14 specified for 'time'. Maximum is 6.
timezone How to time sync MySQL with system time
DST and UTC_TIMESTAMP
timestamp column behavior
Curdate() returning one day old date
ERROR 1146 (42S02) at line 12: Table 'mysql.time_zone_name' doesn't exist
Mysql ADDTIME can it do this ? Daylight savings time issue
converting timezone for data in specific table
TIMESTAMPADD and Daylight Savings Time issue???
Probable timezone problems: can anyone confirm and offer a solution?
timezone tables convert_tz giving null even after updating time zone files
time_zone_id CONVERT_TZ time_zone_id reliable?
tiny Oracle CLOB in MySQL?
tmp how to solve this complex query
question about create a table
/tmp folder getting filled with #sqlXXX.MYI and #sqlXXX.MYD files
tmp tables Optimising max_heap_table_size & tmp_table_size
tmpdir ERROR 126 (HY000): Incorrect key file for table
tmp_table_size Changing tmpdir causes InnoDB to break
top n Top n Scores
Selecting max for each day
topn [SQL] Left join order
Select N per Value
touch Poor Performance with tables over 1Million entries
transaction Transaction/Locking Question
transaction rollback mysql innodb transaction concurrency
transactional what is transactiona and non transactional table in mysql?
transcoded column specific collation issue
transcription Checking for exact match in row
transpose Query Slowness
tree Multi Level Sorting - Queries Question
Modifed Preorder Tree Transversal Child Roll Up (including grandchildren)
Building a widget/graph from mysql view
tree walk How to transform NESTED SETS to XML?
trigger Trigger Replication is not same as in the documentation
Delete record with backup
trigger example Mysql
Date check on insert.
trigger limitations Triggers & sProcs
triple master Multi master problem
trx limitation on request per second
tuning MySQL Performance Tuning on my server
High CPU use (spikes) and Page Faults in VM
MySQL Performance Tuning Help
Optimal Mysql Configuration (my.cnf)
tutorials Self-Help
tv listing What Method is Best
typos Strange results when doing a Fuzzy comparison of two email addresses with the match/against function
union Paging on Union queries
N-to-N Model: Table Size vs Complexity
Opinions on this schema please =)
Slow query - help me optimize ?
INNO DB performance problems with temporary tables
join in union
Poor performance with an "OR"
Rewrite Full Outer Join into Subquery
unique Question related to unique key
update Performing multiple updates and selects
update subselect calculating total products in each category
upgrade Upgrade from 5.0 to 5.1
Can replicating between versions cause crashed tables?
Moving Mysql to a new server
replication from 4.1 to 5.5 and character set change
upgrade dual master Master Master Replication Upgrade from 5.0 to 5.5
upgrade via dump botched data post-upgrade
user MySQL users question
Why doesn't root get full privileges?
Revoke privileges from user issue!
using index InnoDB CPU Spikes
Use of DISTINCT in INNER JOIN
using index for group-by Index optimized left join with group by
utf8 utf8 inputs store as html entities, how to retrievesubstr of utf8 inputs?
Mixed encoded DB Latin1 & UTF8
Re: Korean characters displaying as ???
Storing UTF-8 strings in MySQL Database
Character encodings issues with php, mysql, apache
load data character set question
Problem with Batch Import
what is the step to convert a db from latin1 to UTF8
UTF-8 problem
Require suggestion for changing character set in Master master replication setup
Storing Hebrew strings Ok, but gibberish when pulling data on another server
Migrating from latin1 to utf-8
problems with charset
replication from 4.1 to 5.5 and character set change
Windows: problem with unicode after update
utf8 bom Proper display of special latin1 characters in Powershell / MySql client ?
utf8mb4 Arabic text in mysql Varchar row
Charset and Collation Question
uuid UUID as a primary key
utf-8 uuid varbinary
varchar InnoDB log group capacity error
Join Statement with math operation
varchar index mysql search performance
varchar vs tinytext VARCHAR vs. TEXT - some performance numbers
varchar(255) Outfile Using too much disk space
variance What is the SQL equvalance to VARIANCE
vb6 text How to store long string from VB6 to MySQL database
version diffs Simple performance question - differs on 2 computers
version incompatibility Need advice to Setup replication server (INNODB)
vertical partition JOIN vs Denormalize table vs Vertical partition
JOIN, LIMIT, ORDER performance problems
Error while creating the table in InnoDB
Cascading deletes
vertical partitioning RAM requirements- new server
Partition by threadid or postid?
view use index on a view
view charset Database migration failing.
views View insertion failing
Can we expect an enhancement for derived table merge optimization?
vista perl script hangs on query with where clause
wait_timeout how much time can i set in wait_timeout in mysql(wait_timeout variable)
Performance Issues - errno 12 on MySQL5.0.45/Windows Server 2003
MySQL 5.1.36 on FreeBSD 7.2 amd64/i386 not honoring wait_timeout
MySQL Timeout
Does a too many connections error always really mean it?
Close conections
Can the use of Ephemeral ports be disabled?
web Mysql RAM
where Problem with search when add BETWEEN to query
wheres write trim into INSERT and SELECT Queries
Not working in MYSQL5.1
wide rows Innodb with HUGE row of varchar(500)s
width Display Width Clarification (numeric data types)
windows data dir Where in the harddisk?
Where are the databases?
word boundary help in select ... where ...like...
wordpress get info about a mysql call
world db online sample database to test MySqL queries against?
wrap around table combine this 2 simple querys into 1 query for performance.
combine this 2 simple querys into 1 query for performance.
wrong index simple uses of order by datetime keep causing 'using filesort'
x 8 CPU Cores.....only 1 or 2 being used at the same time...
xss Two usefull functions(XSS/SQL injection).
Text box security
Assistance with securing input
yashinori matsunobu Disaster Recovery with master-master replication
zerofill Display Width Clarification (numeric data types)
search for query that result one random url from domain