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

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3k views

What max_allowed_packet is big enough, and why do I need to change it?

I have MySQL (5.5) in master-slave setup and created another slave server. I stopped the original slave, dumped the data, copied and reimported and it worked fine. I noted the master_log pos of the ...
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1answer
78 views

Update the host field in Grant privileges in mysql

I have an existing table and I want to update host part in privileges using Grant command mysql> show grants -> ; ...
0
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0answers
34 views

Is there any way to set server-wide and schema-wide default row formats for InnoDB tables in MySQL?

Is there a way to set server-wide and database-wide default row formats? Currently it seems that I must specify ROW_FORMAT in CREATE TABLE or ALTER TABLE statements. Am I reading the documentation ...
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0answers
69 views

How to set up a pivot table view?

I have three tables: Entry Manager Employee The Entry table has as date field and a bunch of other fields about the entry including the emp_id. Manager Table has columns: Manager_id ...
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0answers
236 views

Fastest way to perform simple operations on 1 million rows

I have a simple table with more than 1 million rows in an InnoDB MySQL table. Here are the steps that I need to perform on each row: SELECT * FROM tbl where work_done=0 make some data processings ...
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0answers
20 views

Anyone know the fix for an older innodb inspection query

This post talked about an information_schema query to give you a nice report of how much percentage wise indexes are fitting into the buffer pool The query looked like > SELECT `schema` ...
0
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2answers
343 views

How to enable the Federated/FederatedX storage engine on MariaDB 5.5?

I upgraded from MySQL 5.1 to MariaDB 5.3 and then to 5.5 on a Windows machine. Everything works well, except I can't enable the federated storage engine. With MySQL 5.1 and MariaDB 5.3, I just added ...
9
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3answers
409 views

Fastest way to change a 600GB table indexed key datatype from INT to BIGINT

I need to change a datatype from INT to BIGINT in a 600GB MySQL table. The column has a unique index. I might be good with unsigned INT, but I assume changing to that or BIGINT will be pretty much ...
0
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1answer
50 views

How to make slave is in sync with master in tungsten replication?

we are using Tungsten master to slave replication in MySQL. we have configured this setup very long back. from last week onwards slave is in lagging with master around 5 to 10 binary files. we have ...
0
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1answer
119 views

Replication - Binary log parsing(Tableid generation, ON DELETE CASCADE handling, Changed columns for update event)

I am using MySQL 5.5 with InnoDB engine. I have set binlog format as row-based replication. I have some doubts regarding replication: 1) How is the tableID generated? Is it stored somewhere? 2) ...
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1answer
4k views

Function returning “No data - zero rows fetched, selected, or processed” in MySQL 5.5

I have upgraded MySQL version to 5.5.16 After upgrading, some of the functions are giving warning as No data - zero rows fetched, selected, or processed. In those functions, cursors are there, but ...
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1answer
73 views

How to prevent Cartesian joins when value can be in either field?

I have a table of articles where the same article may be presented to different audiences with slightly altered text depending on the user's access level. When this occurs, the article will have the ...
1
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1answer
77 views

Change normal user to admin in MySQL

I have set up a MySQL database. My problem now is I can't add new users with the user I have created. I try to grant access but I can't still add new users to my system. I use Workbench to add new ...
0
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1answer
31 views

Count issue in Mysql

I query a table SELECT COUNT(*) FROM sf_guard_user_group return count 1 but table has total 28 records. But if I test it via putty from another machine, it shows count 28. Help to sort out.
4
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1answer
2k 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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0answers
77 views

how to update current row value by selecting previous row value in php mysql

How can i update data of current row with selecting data of previous row in php mysql. I have tried following query but it showing me error. update sales_tracking set sales_tracking.opening_units = ( ...
0
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0answers
91 views

Booted by MYSQL Error (2003) 10060 mid way through work

I was working on some queries and then my HeidiSQL froze, I tried to reboot the connection and I get good old MYSQL Error (2003) (10060). It worked just fine before that. I haven't made any firewall ...
0
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1answer
33 views

Cannot create stored procedure

I have the following piece of statement entered into MySQL5.6 Command Line Client. However, the following error was received. I haven't even been able to add in END// Delimiter; after the select ...
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0answers
34 views

How to move partitions between filesystems

We have ~9TB MySQL database which consists from a few tables which are partitioned by day. Sum of daily information is ~20GB. Database is practically write only. There are at most tens of queries ...
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0answers
22 views

Cloning rows with minor changes

I am attempting to clone a row in the database, not that difficult. However the row has a reference to another row in the database that when inserted needs to use a different value, perhaps provided ...
1
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3answers
5k 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 .
3
votes
1answer
96 views

How to store static list of hashes in MySQL effectively?

Problem: I have a list of pairs (md5_hash, id). I want to store the data in MySQL and I want to make queries like this SELECT id FROM table WHERE md5_hash = <some_hash> The number of pairs ...
0
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0answers
28 views

Accessing Database from Slave server

I have an application running in one server eg: My Server's Ip is 192.168.10.10, and I have the MySQL database server in the same machine. The application connects database server as localhost. ...
2
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1answer
37 views

Unknown column error with an index

I created a simple index associated with a timestamp column CREATE TABLE `data` ( `id` INT(11) UNSIGNED NOT NULL, `ticker` VARCHAR(16) NOT NULL COLLATE 'utf8_unicode_ci', `comment` TEXT ...
5
votes
1answer
376 views

Possibilities to speed up InnoDB INSERTs and UPDATEs

My website retains user sessions in an innodb table. This usually works well, but a few hundred times a day, the INSERT and particularly the UPDATE statements run slower. I'm monitoring when, and it ...
2
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1answer
137 views

MySQL table architecture

Background information: I have a table containing upload information, every day I get more and more uploads but most of the queries I run center around information gathered within the last 12 months; ...
3
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3answers
1k views

Issue after moving the ib_logfile1 and ib_logfile0 files

I wanted to increase the innodb_log_file_size for better performance. And I increased it from the default value to 256 MB. As usual I got the error saying InnoDB: Error: log file ./ib_logfile0 is of ...
0
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1answer
80 views

How to drop a column named 'column'? [closed]

I need to delete a column named "column" form a table but the standard: mysql> ALTER TABLE table_name DROP COLUMN 'column'; returns: ERROR 1064 (42000): You have an error in your SQL syntax; ...
0
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1answer
71 views

Using an enum index to limit records

A common issue, just not sure on the keywords. I have a table of assessments (14k+ records). Each assessment can be in many different states ('draft', 'proofing', 'amends', etc... and 'done'). Most ...
0
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1answer
102 views

MySQL 1366 Error on Replication Slave

I've got two pairs of servers (each identical hardware and OS) with replication running on both pairs. Running MySQL 5.5.34 on Windows Server 2008 R2. I'm trying to track down a problem that has ...
1
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1answer
70 views

How and where do I upload a mysql database?

I am new to Ubuntu (server edition) and mysql. How do I upload (import) an existing database with a MYSQL or (mysql.zip) extension that was downloaded from a web host (cPanel?) I do not have any of ...
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2answers
179 views

How can I return column names in dot notation in MySQL?

I want to return column names into a table. But I also want to avoid redundancies like 'id' and 'id'. I did: INSERT INTO columns(name) SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE ...
2
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1answer
105 views

Is there a way to achieve Workload Management in MySQL?

Is there a way to set up Workload Management in MySQL (in particular v5.5 on AWS RDS)? By Workload Management I mean the functionality implemented in e.g. Teradata, RedShift that allows ...
0
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1answer
66 views

how auto_increment work in mysql

im confused here , i create a table and have 2 columns id and name. Now id is primary key , not null and auto increment. Suppose i fire: insert into table (name) values('test'); this will give me: ...
1
vote
1answer
697 views

MySQL: Alter Table on very active table gives “Waiting for table metadata lock”

At my work, we've recently upgraded to MySQL 5.5 and since then, have been bitten a few times by the new (and intended) behavior of metadata locking. Basically, whenever we run an ALTER TABLE ...
0
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1answer
196 views

How to update a table by count from another table?

I have two tables as CREATE TABLE country_statistics ( id int(11) NOT NULL AUTO_INCREMENT us int(11), uk int(11), ca int(11), PRIMARY KEY(id) ) ENGINE=InnoDB DEFAULT CREATE TABLE entries ( id ...
0
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1answer
49 views

MySQL Partitioning: why it's not taking appropriate partition

DROP TABLE temp; CREATE TABLE `temp` ( `CallID` bigint(8) unsigned NOT NULL, `InfoID` bigint(8) unsigned NOT NULL, `CallStartTime` datetime NOT NULL, ...
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0answers
39 views

Is it better performance wise to check if a field needs update if you know the record does

In the queries we use all the records in one table that has data which needs to be placed in a another system had a Insert, Update and Delete flags (i, u, d being 1 in the record), this way we can ...
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0answers
63 views

Query Execution Plan for MySQL

In Microsoft SQL Server you can see Execution Plans for queries to see how a query is executed, what joins take the most time and see any missing indexs now i want to do the same for MySQL scripts ...
1
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1answer
48 views

Create user for alternate port

I am running a private MySQL instance on WebFaction WebFaction is a shared host who provides both for their public MySQL instance and for your own private MySQL instance. The private instance is a ...
0
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0answers
272 views

mysql doesnt have write access in data dir?

I am running a MySQL on my Windows 7 64 bit development machine at work and I can't seem to get around a database corruption issue. In my unit tests it is telling me that the storage engine (which is ...
0
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2answers
221 views

How to use OR in query with priority?

In a simple query like SELECT * FROM table WHERE id='x' OR id='y' How to give a priority to get only one of the WHERE clauses? I mean getting rows with id='x'. Only if there is no row, get row ...
0
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0answers
285 views

Incorrect information in .frm file after a power outage?

CentOS release 6.3 (Final) x86_64 mysql Ver 14.14 Distrib 5.5.31, for Linux (x86_64) using readline 5.1 SHOW SLAVE STATUS\G: Slave_IO_Running: Yes Slave_SQL_Running: No ...
0
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1answer
48 views

Join on with modified ON

I am trying to create table with summary of few other tables. All solutions i came up with are very slow and clearly not optimal. Initially I tried with multitude of subquerries but that was very ...
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0answers
27 views

table scheme definiation it this way that insert duplicate into another table

I have a table in which there is a column name with SP varchar(10) NOT NULL. I want that column always to be unique so i created unique index on that column . My table schema as follows : CREATE ...
1
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1answer
1k views

How to run a SELECT query within while loop in PHP?

Within a SELECT query via PHP while loop, I need to run a mysql SELECT query as $result1 = $mysqli->query("SELECT * FROM table1"); while ( $row = $result->fetch_assoc() ) { if ( $row['X'] == ...
1
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2answers
127 views

Breaking Semisynchronous Replication in MySQL 5.5

I've set up Semisynchronous Replication between two MySQL 5.5 servers running on Windows 7. My application is running and updating the database of the master server and same is being updated in the ...
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2answers
1k views

Unable to drop the table since its showing waiting for meta data lock

We are trying to drop one table but it's getting hanged, and when we see the 'SHOW PROCESSLIST' command it's showing as 'waiting for meta data lock'. Even we are unable to perform any operation on ...
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1answer
931 views

Upgrading MySQL 5.1 to 5.5 on Centos 6 without removing dependencies

I'm trying to upgrade MySQL 5.1 to 5.5 using yum/rpm combo (yum to remove MySQL 5.1 and rpm to install MySQL 5.5). Most instructions I've found suggest to do first: yum remove mysql mysql-server ...
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0answers
317 views

MySQL InnoDB slow inserts

I'm currently struggling with an MySQL Community Server 5.5.27 when inserting large numbers of rows into a table. We're running a 24 core Intel Xeon machine with an SSD software raid array. I did some ...