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

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132 views

restricting users to rows they created

To educate myself in PHP and mysql, I am making a browser based rpg game. This game will allow any number of users to register an account and, once registered, they can add, edit or delete champions ...
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3answers
2k views

InnoDB insertion faster

I'm a graduate school student researching OLAP with Mondrian OLAP. So I want to insert data into InnoDB (MySQL 5.5) faster at the initial loading. In this environment, the only user is me, so I think ...
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1answer
1k views

MySQL Slave Relay Logging but not logging Binary Log

I have a master slave setup both mysql 5.5, the setup is fine except that the slave won't Binary log to the standard mysql-binlog only to the relay logs. I fear this may be due to my lack of ...
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2answers
628 views

How to concatenate a column after x rows?

I have a table with columns object varchar(255), frequency tinyint(3) unsigned, I want to concatenate the objects if the sum of frequencies reach a value. Currently I am doing this in PHP as .. ...
3
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1answer
145 views

Backup and off-site restore setup

I've been reading a lot of threads about different backup options for MySQL and was hoping for some more insight so I can settle on one. Our current situation is ~100 GB of InnoDB and MySAM data in ...
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2answers
2k views

Large files in wamp\bin\mysql\mysql5.5.24\data directory

I have discovered these files located in the wamp\bin\mysql\mysql5.5.24\data folder on my Windows 2008 server. They are consuming about 22 GB on a 40 GB drive. I am using a LMS called moodle, that ...
3
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1answer
211 views

how to add removed partition?

This is the structure of my table: -- Table: t_keyword_conversion_ga -- Create Table: CREATE TABLE `t_keyword_conversion_ga` ( `id` int(11) NOT NULL AUTO_INCREMENT, `own_domain_id` int(11) DEFAULT ...
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2answers
3k views

Is it bad to create many mysql temporary tables simultaneously?

I need to make heavy statistical analysis to deliver some data to users. Currently, I catch the data from mysql and process them via PHP arrays. However, mysql temporary tables are quite better ...
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1answer
3k views

Enabling “log_queries_not_using_indexes” disables “long_query_time”?

I noticed that, in Mysql, when enabling log_queries_not_using_indexes, slow_query_log and long_query_time, the generated slow query log file will contain a lot of queries even if the query time is far ...
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1answer
502 views

Does mysqld wait for init-script code to complete before opening the instance?

I'm trying to automate the execution of an application code at MySQL startup. The init-file server option seems handy and I need to know if mysqld waits for all the code in the init-file to complete ...
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3answers
9k views

How to Restore data from binary log

I am trying to restore some lost data , but I am not having its backup .So I am trying to restore from the binary log .Please explain how to restore from the binary log in mysql .
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1answer
238 views

What's the most unsafe MySQL configuration?

I have MySQL 5.5.27-29.0-log instance running specifically for Jenkins. Since tests data is always recreated during setup, ACID is unnecessary and I'm hoping to sacrifice it to gain more performance. ...
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1answer
369 views

Unable to take backup of mysql database using Xtrabackup

I am trying to take mysql backup without any downtime but unable to take the backup using Xtrabackup . Actual Database is almost about 40+ GB in size. I am trying to first satisfy myself. Hence, I ...
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0answers
540 views

MySQL cluster stuck in start phase 4, how to proceed?

Over the weekend our cluster we set up for evaluation had one of its data nodes lose network connectivity briefly. This was while another data node was in the middle of a restart (which had been going ...
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0answers
152 views

Please help configure my Mysql for 12GB 4cores server

I use a dedicated server with 12GB memory and 4 core CPU with Ubuntu 12.04 LTS (x64). This not just a database server. MySQL appears to be restarting frequently, I think I can tune the config to ...
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1answer
38 views

Not able to create a new table new_table from t1 by comparing primary key values of another table t2 in MYSQL

I am trying to create a new table new_table from t1 by comparing primary key values of another table t2 ie, 1) created table new_table 2) gave the query insert into new_table select a.* ...
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1answer
339 views

Restriction on self referencing on insert in MYSQL?

How to restrict insert on adding self referencing rows in a recursive relation table (a table contains foreign key points itself). mysql> SELECT * FROM Employee; ...
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1answer
432 views

How to Update same table on deletion in MYSQL?

In my Database I have a table: Employee with recursive association, an employee can be boss of other employee. Following is query I used to create table: CREATE TABLE IF NOT EXISTS `Employee` ...
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0answers
106 views

How to create multi volume file backup using symantec backup.exec

I am using symantec backup .exec for backup and restore in mysql server . Now I am in need to take larger database backup in tape .But it exeeds the tape storage and I am trying to create a multi ...
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2answers
2k views

MySQL 5.5 Fail start Fedora 16

I installed mysql and mysql-server from the repos (MySQL version 5.5). Then tried to start it, but got an error. [root@server]# service mysqld start Redirecting to /bin/systemctl start ...
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1answer
303 views

mysql session logging tables

I've been building a session logging system for our sites. We get around ~15m hits a year and at the moment we're really only interested in stats about people who logon to our sites. Our table ...
2
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3answers
898 views

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
672 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
393 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
2k 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
2k 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: ...
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1answer
196 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
266 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 ...
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1answer
270 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
183 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 ...
1
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1answer
154 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 ...
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1answer
858 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
137 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
2k 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
1k 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
324 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
334 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
307 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
694 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
305 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
395 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 ...
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3answers
515 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
21k 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
6k 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
764 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
519 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
736 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
59 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 ...