MySQL 5.5 brought many performance enhancements and expanded the feature set of the popular open-source RDBMS.

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how to install mysql on mac?

My Mac runs Mac OS X, version 10.7.5., so it's a 64 bit system. First, I downloaded mysql-5.5.28-osx10.6-x86_64.dmg. Then I double clicked mysql-5.5.28-osx10.6-x86_64.dmg, it's mounted, and shows ...
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1answer
499 views

Query to take partial backup in MYSQL

I tried to take full backup in mysql using enterprise backup by using the command mysqlbackup -u root -p --backup-dir=g:\full_bck backup But I could not take backup of a single database , I ...
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1answer
298 views

How to removing or reduce the size of redo logs in MySQL cluster

Can anybody tell me that how can we reduce the redo log file size or can we remove the redo log file size in MySQL Cluster and also what will be the impact of it on performance of cluster.Also can we ...
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1answer
1k views

How to COUNT number of rows with LIMIT?

I want to catch X rows, thus, I set LIMIT X; but how can I simultaneously count the total number of rows too? Currently, I use two separate queries to do so as SELECT COUNT(*) FROM col WHERE CLAUSE ...
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1answer
1k views

Retrieve double data type value in non exponential form

Is it possible to retrieve non-exponential value in double data type column? After the width of the column is increased to 15 it shows the values in exponential form. Now I get the following: ...
2
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1answer
185 views

innobackupex is failing while exporting backup

I am using perl script which is working fine in one of my other box which used to take individual schema backups & finally take all schema together using percona innobackupex. I have following ...
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1answer
221 views

How can I change the timezone in MySQL?

In a MySQL DB, I have two varchar fields. One is for date and one is for time. I need to change the time from CST to GMT. In MySQL how do we convert the combination of these date and time fields from ...
5
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1answer
266 views

Migrating MySQL to new server

We have a MySQL 5.1 instance running on Windows Server 2008 R2 x64 (Server A) replicated to another MySQL 5.1 instance on Windows Server 2003 R2 (Server B). We have a new MySQL 5.5 instance on ...
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1answer
158 views

MySql - selecting into file and re-loading it with special characters

I have a MySql table called twitter_statuses which as the title suggests holds twitter statuses. here is the table structure. this table contains all sort of characters in the text column, and some ...
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1answer
142 views

MySQL Cluster Steps To Recover Data If Catstrophic Failure Occurs

I want to know if a catstrophic failure occurs (like a power outage), and all nodes in MySQL Cluster are shutdown in cluster then data will be lost even though a backup was taken? Or it possible that ...
1
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1answer
710 views

`show procedure status` doesn't list all of the procedures?

mysql-server-5.5.28-1.el5.remi I'm pulling my hair with this problem: only EMS SQL Manager can list all of my store procedures (1763). mysql client, mysql-workbench, Navicat, ... only see some of ...
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1answer
126 views

Handling error of foreign key

How to set a FK value NULL upon receiving error for foreign key constraint? Consider a simple table a CREATE TABLE test ( id int(11) NOT NULL AUTO_INCREMENT ex_key int(11), FOREIGN ...
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3answers
1k views

MySQL optimization - year column grouping - using temporary table, filesort

I have a transactions table which is having 600,000 records, I need to list the count for the dashboard on financial year basis. The table used is MyISAM. I tried adding index for the transaction date ...
0
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1answer
924 views

How can I enable my-huge file on windows server?

I installed Windows Server 2008 and MySQL 5.5. Now I need configure MySQL for huge InnoDB tables and a lot of connections. I see that on my Windows Server, there is a my-huge file(configs files that ...
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1answer
300 views

MySQL-5.5 InnoDB memory issue

Version in use is mysql-5.5.24. In the Enterprise version of MySQL innodb_buffer_pool space is released after a while, however this does not appear to be happening in the community version. I am ...
4
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1answer
3k views

MySql - Changing expire_logs_days without restarting the server

I'm using MySql 5.5. Is it possible to change expire_logs_days and have the changes take effect without restarting the server?
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1answer
295 views

Mysql 5.0 on Windows 2008

I have a problem with MySQL on Windows Server 2008 x64. This is the first time I've installed MySQL 5.5 with performance problems. I decided to go back to the older version that worked well with ...
2
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4answers
287 views

Does my table violate normalization rules?

I am developing an emulator for a game. My item table looks like this: -- ---------------------------- -- Table structure for `items` -- ---------------------------- DROP TABLE IF EXISTS `items`; ...
2
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2answers
511 views

Does MySQL 5.5 support shared database with separate schema?

I am developing a SaaS based product using MySQL 5.5 as the backend database. I want to keep shared database for all the tenants, but separate a database schema of each tenant. There would be a single ...
2
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1answer
268 views

Null Values and Performance

I always try to build the database avoiding any NULL values in my tables, and I have successfully had done this so far. (Hey, I am very new to database design.) But still there are times when saving ...
3
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1answer
313 views

Do I need to index a key that I partition by?

I have an InnoDB table of customers, partitioned by KEY, with each partition being one US state. I have an index on phone number, and the performance is great. We also need to SELECT by last name in ...
5
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3answers
381 views

MySQL varchar(255) limitation & Anomaly

I have defined a column in my MySQL database as : ALTER TABLE `my_table` CHANGE `desc` `desc` VARCHAR( 255 ) CHARACTER SET latin1 COLLATE latin1_swedish_ci NOT NULL However, when I enter text ...
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1answer
17k views

intermittent MySQL crashes with error “Fatal error: cannot allocate memory for the buffer pool”

Added on edit, 2013-05-29: Because this is a long question and discussion, here's a short summary of the question and the solution. I had problems running MySQL and Apache on a small Linux server (1 ...
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3answers
5k views

MySQL InnoDB crash post-mortem

MySQL crashed on me this morning. With the exception of the standard MySQL included databases everything I use is InnoDB. I attempted to restart the MySQL daemon but it failed twice. I then ...
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1answer
51 views

Query from database

I have a table named mip. The table has primary key id, a foreign key product_id and a column usage_type. product_id is a primary key id to a table named product. It is one to many relationship from ...
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1answer
638 views

Does TRANSACTION/COMMIT/ROLLBACK only work on certain MySQL engines such as InnoDB?

Are transaction functions only relevant for particular database engines on MySQL, or are transactions supported under all MySQL engines, including MyISAM and InnoDB? someone says here that ...
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0answers
442 views

MySQL import file with no column delimiter

Is there a way to use the mysqlimport command on a file that has no column delimiters? I would like to import the ctl file used with the sqlloader for Oracle
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1answer
607 views

MySQL Master-Slave Replication Cross Database

I am setting up Replication for cross Database as i have set 2 variables in Slave' s my.cnf as replicate-do-db=database_name and Replicate-wild-do-table=database_name.% ,But i am not able to get ...
0
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1answer
58 views

Move databases on same Mac

I have just updated my MacBook to Mountain Lion. Since then, my MAMP installation does not work properly so I decided to use the build httpd/php stuff. For this, I have additionally installed a new ...
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0answers
83 views

How to profile individual queries using PERFORMANCE_SCHEMA

I've been looking at SHOW PROFILES, which seems ideal for what I am doing. However, I've noticed a warning that SHOW PROFILES is being deprecated and that PERFORMANCE_SCHEMA should be used instead. ...
2
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1answer
86 views

Count total where owner_user_id = some_value and deleted_by_owner = 0 or to_user_id = some_value and deleted_by_to = 0

I didn't know if this is possible using just a query or if I need some procedural logic on this one. I have this table: CREATE TABLE `default_messages_users` ( `id` int(11) NOT NULL ...
4
votes
2answers
9k views

innodb_flush_method=O_DIRECT vs O_DSYNC performance impact on ext3 with LVM disk partition

In one of my production environment, we have two instances running on a RedHat cluster, with one production instance associated with the cluster. We have 125G main memory with 24G InnoDB buffer pool ...
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0answers
83 views

MySQL replication backup

How to take MySQL Master-Master and Master-Slave replication backup?. I have setup Master-Master replication with a separate slave for each master on Ubuntu. What happens if, I issue or schedule ...
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1answer
4k views

Some MySQL slave errors?

Master version: mysql-server-5.5.14-1.el5.remi Slave version: Percona-XtraDB-Cluster-server-5.5.24-23.6.340 Binlog format: ROW based I'm using PRM to setup HA for MySQL. Sometime, MySQL slave ...
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1answer
517 views

MySQL Replication Error, can't stop slave

When I run command SHOW SLAVE STATUS\G, I see Slave_IO_Running : 'Yes' Slave_SQL_Running : 'No' What I've usually done to fix this is to run STOP SLAVE; SET GLOBAL sql_slave_skip_counter = 1; ...
4
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1answer
3k views

Setting up MySQL Cluster on Two Systems

I am attempting to setup a MySQL Cluster. I have the folllowing setup one management node two data nodes another machine on which two more nodes reside Below is the config.ini file: [ndbd ...
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1answer
221 views

Compare MongoDB and MySQL

Can anyone help me to make right decision for choosing scalable and reliable database? I have to create 3-4 tables with around 200 columns each and these tables will have around 5000 data records. As ...
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0answers
70 views

memc_delete called from a MySQL trigger loop fails randomly

I'm calling memc_delete from a MySQL trigger's code. The call is inside a loop. Logging the results, I see that memc_delete sometimes returns 1 (ok, memcached entry deleted) and sometimes returns 0 ...
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3answers
307 views

Finding differences between a master and slave when pt-table-sync fails

I have a table that's showing some differences on a master and slave according to pt-table-checksum (PTC). I've found some verifying differences beyond that. Certain tables in the mix have composite ...
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1answer
157 views

Get and count all blog posts and all users that fits a LIKE condition (two sepparated queries)

I've this tables: -- -- Table structure for table `default_cmvblog` -- CREATE TABLE IF NOT EXISTS `default_cmvblog` ( `id` int(11) NOT NULL AUTO_INCREMENT, `title` varchar(100) COLLATE ...
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1answer
1k views

MySQL 5.5 not starting after master-master configuration

The following master-master configuration worked on MySQL Server 5.1.x(Ubuntu 10.04). Master1(192.168.2.80) ################################## #MySQL Replication ################################## ...
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2answers
421 views

MySQL - How much physical space will be reduced by changing the column type?

Lets say I have the following table: CREATE TABLE `my_table` ( `id` int(11) NOT NULL AUTO_INCREMENT, `user_id` int(11) NOT NULL, `relationship_status` varchar(48) CHARACTER SET utf8 COLLATE ...
0
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1answer
177 views

How to set unique columns combination

see this table: CREATE TABLE IF NOT EXISTS `default_messages_users` ( `id` int(11) NOT NULL AUTO_INCREMENT, `message_id` int(11) NOT NULL, `owner_user_id` int(11) NOT NULL, `to_user_id` ...
1
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1answer
733 views

MySQL INSERTs waiting for UPDATEs (MyISAM)?

In show processlist;, MySQL 5.5, we see that INSERTs tend to wait for UPDATEs to complete before they can proceed. This is on MyISAM tables. We tried INSERT HIGH_PRIORITY and UPDATE LOW_PRIORITY. ...
4
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1answer
74 views

Will these queries return the same results?

I have this simple query: SELECT friend_id FROM default_friend WHERE user_id = 1 And the results are below: +-----------+ | friend_id | +-----------+ | 2250 | | 4901 | | ...
6
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1answer
4k views

When to switch from MyISAM to InnoDB?

We have a MySQL 5.0 server running all tables as MyISAM. We have two slaves that, in the last month, we have upgraded to MySQL 5.5. Their tables are also still MyISAM. My original plan was to upgrade ...
2
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2answers
116 views

How to see what was executed in the database via binlogs for specific date?

I am trying figure out how to "query" binlogs to see what was exectued in the database for a specific date. For example, if I execute mysqlbinlog binlog then the thing just runs forever and it is had ...
2
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1answer
154 views

Need some help with this query get all status and their associated comments of me and all my friends

I've several days dealing with this query but can't get it to works as I want. This post is related to this one Several values from different tables in which I tough found the solution but I was ...
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1answer
120 views

Several values from different tables

I'm totally lost here and not know how to get this to work and hope any can help me here. I have several tables: default_users, default_profiles, default_status, default_comment and latest ...
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1answer
182 views

Is possible to optimize this query or it's already optimized?

I've three tables: default_users, default_profiles, default_friend. This are the SQL for each one: -- -- Table structure for table `default_users` -- CREATE TABLE IF NOT EXISTS `default_users` ( ...