MySQL : Open-Source, Relational Database Management System

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6
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1answer
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MySQL or Oracle Associate Certification?

I have 15+ years in software development and 7+ in web development, and I want to get a certification in another area, like DBA. I have 7+ years of experience like MySQL developer. Which is better for ...
2
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3answers
2k views

How do I get % progress for “type db.sql | mysql”

I am doing: type db.sql | mysql and the console output is nothing. I see the ibdata1 file growing, but I don't know how many GB it will grow to. I would like to see a % progress indicator of some ...
1
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1answer
162 views

setting up a local database to be updated from a master database

I'm looking for an efficient way to keep multiple databases (on different servers) sync with a master database (also on a different server). Mind you I only need a one way sync (from master to all ...
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1answer
217 views

How to keep MySQL general_log after I restart my computer?

I use a statement set global general_log = 'ON' to enable the general_log on my computer. After I restart or shutdown it, I have to run the statement again. How can I config MySQL write general log ...
3
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1answer
635 views

Do I have duplicate key indexes?

CREATE TABLE relations ( object_id BIGINT(20) NOT NULL PRIMARY KEY, object_term BIGINT(20) NOT NULL, UNIQUE KEY link(object_id, object_term), CONSTRAINT fk_term FOREIGN KEY(object_term) ...
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2answers
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MySQL Sharding vs MySQL Cluster

Considering performance only, can a MySQL Cluster beat a custom data sharding MySQL solution? sharding = horizontal partitioning When I refer to sharding, I'm considering sharding made in the ...
5
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3answers
5k views

MySQL general query log performance effects

One of our customers who has a somewhat problematic web application would like us to log all the queries for a period of 24 hours. I wouldn't know how much data it will actually write. The amount ...
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1answer
93 views

mysql server password change while restoring

I restored all database backup from another server's dumpfile to my machine. At the end my mysql server's password changed to that mysql server's password. Why it got overwritten? What i need to do to ...
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2answers
274 views

Is it advisable to have MySQL Master/Slave running on the same physical server, on the same mysqld, sharing the same disk?

my Use-Case : The solution I am developing is very data oriented. I run a cron job every 3 hrs to read lots of records from a file, process them and store them in the database. I also need to ...
7
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5answers
16k views

MySQL : DROP TABLE Starting with a Prefix

EXAMPLE : I have more than 30 tables starting with a prefix "dp_" and about 12 starting with "ex_". QUESTION : How can I drop all tables starting "dp_" in one query ?
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2answers
6k views

Does MySQL support replicating all databases?

I’ve been doing some investigation into properly configuring MySQL replication. From what I understand after reading the documentation, you can only replicate specific databases, and each database ...
4
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4answers
986 views

What's the equivalent of --safe-updates of mysql in MS SQL Server?

In MySQL, you can use the feature called --safe-updates (--i-am-a-dummy) to limit the number of rows updated per query. http://dev.mysql.com/doc/refman/5.0/en/mysql-tips.html#safe-updates Is there ...
4
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3answers
689 views

Separate databases for front-end and back-end

The site I am working on has a lot of backend/cron activity, so there are between 5 and 15 queries being executed every second of the day. This can slow down page loads by a second or more. I was ...
6
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3answers
678 views

Is there a need to keep refreshing the indexes from time-to-time?

This question is common for all the database products I use, viz. SQL Server, MySQL, Oracle and PostgreSQL. I have created a fresh database and the tables, at present, have no records. I have created ...
3
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1answer
1k views

Master and Slave having same id's

I am working as a remote DBA for some of the production servers. There was replication from Master to Slave. There is something changed in the scenario they have made one of the Slaves as master ...
2
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1answer
169 views

How can I best combine “get categories” and “has user access”?

I was wondering if it's possible to create a query for the following problem. I only want to select categories from the (MySQL) database (if the user has access). A user has multiple roles; A ...
1
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2answers
176 views

Two master databases for two separate apps

We have two different websites one is hosted in asia datacenter called it asiadata.com and other site is hosted in europe datacenter called it europedata.com. Currently we have only one master ...
6
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4answers
3k views

Incomplete mysqldump

I'm trying to run mysqldump to create a database snapshot, and I'm finding it will randomly stop midway, without reporting any error. My database is relatively small (about 100MB) and is using InnoDB. ...
8
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3answers
8k views

ALTER TABLE on a large table with an indexed column

I have a large table with a VARCHAR(20) column, and I need to modify that to become a VARCHAR(50) column. Typically, performing an ALTER TABLE (adding a TINYINT) on this particular table takes about ...
2
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1answer
2k views

Migration from DB2 to MySQL

Does any one have experience on migration from DB2 to MySQL ? Please share with me. I tried googling, but I have not received much information on this.
3
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2answers
691 views

Should I move to InnoDB during a planned migration?

I'm shortly migrating a Debian Lenny webserver to another host and Debian Squeeze. The standard MySQL installation even on Squeeze is 5.1 and therefore would default to MyISAM - I'm inclined to stick ...
1
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1answer
412 views

Why did the MySQL Storage Engine Change on Restore in one scenario?

In my production database life, there was one tragic incident when the MySQL engine type was accidentally changed from InnoDB to MyISAM on restoring a recent backup. The result was that all ...
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1answer
1k views

Problem with MySQL Master/Slave reboot when in replication

There is a master and number of slaves connected to it. Due to some patches, we have to Reboot the Master and Slave. Afterwards, we have to make sure replication is running fine. While doing this ...
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1answer
99 views

What is QP layer?

From blogs.innodb.com: InnoDB Memcached with Binlog Capability In our earlier Labs release, we presented a MySQL NoSQL solution through InnoDB Memcached Daemon Plugin (see earlier Calvin’s and my ...
3
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2answers
3k views

Different MySQL Datafile Sizes After Restoration

I'm quite new in database administration. The database architecture of my current company is master-slave replication. We are using MySQL version 5.0.86. Some weeks ago, we upgraded the company's ...
2
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2answers
364 views

Database Transfer from PostgreSQL to MySQL

Is there any method to tranfer the data and schema from a postgresql database to mysql?
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1answer
385 views

MySQL Grant Permission

I want to Grant a user only INSERT permission. When I try to insert data, it throws the error "Access Denied". What permission do I give a user to use/select database in mysql and how? I have given ...
3
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1answer
101 views

Is it possible to find the values of MySQL variables if I do not have SELECT privileges on mysql.user?

I am getting a 'msyql server has gone away' error sometimes when doing a large binary insert, so I wanted to check the settings on mysql, things like wait_timeout and max_allowed_packet. However show ...
2
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1answer
793 views

BACKUP and RESTORE MySQL Database

I have very specific question. I have seen the instructions on how to backup and restore mysql database using SSH but they barely explain the process when backing up on one server and restoring on ...
2
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2answers
7k views

Set up a MySQL slave using mysqldump to get the initial data

I have a master database which already has some data in it. The tables in the master database include both MyISAM and InnoDB engines. Now I want use mysqldump to dump the initial data of my slave ...
4
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1answer
4k views

What memory should be given to the variables of my.cnf ?

Installing a MySQL server is quite easy. However, after installing, configuring the server is an important task for a DBA. Having 2GB of RAM and 250GB of disk space, how should I tune MySQL server so ...
3
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1answer
877 views

Webapp & MySQL: Row Level Security

I am trying to emulate row level security on a webapp I am developing using MySQL. Using this method: Creating a database with the the required tables where the data pertaining to all the users will ...
1
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1answer
255 views

What is a better way to keep “user online”?

I'm working on software for social network and I plan it to scale a lot. Actually, I'm updating timestamp column every time user clicks, to be sure they're marked as online. When they do not click for ...
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2answers
846 views

MySQL - Changing DB CHARACTER SET

I have a 30GB MySql DB, made of innoDB tables. currently the tables character set is: "utf8_unicode_ci" and I want to change it to "utf8_general_ci", what the best way to do it? currently i'm going ...
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3answers
460 views

How can I select all online friends?

I'm currently working on a social network software written in PHP & MySQL, and it's all pretty fine, but one thing I'm stuck about is online friends. My tables looks following Users ...
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4answers
558 views

MySQL - speed up execution of ALTER TABLE

I have a MySQL DB with innoDB tables. the DB size is about 30GB. I am using ALTER TABLE table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci; to change all the tables characters set and it ...
5
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4answers
10k views

Visualization of MySQL/PostgreSQL table structure as a graph/UML

Is there any program, source code or API that will take a MySQL or PostgreSQL schema and spit out a UML or some other graph visualizing of it?
2
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1answer
1k views

MySQL - How do you enter a record with only whitespace “ ”?

I want to enter the record with white-space as a record in MySQL. I had tried to enter it through shell and phpmyadmin, the record enters but when I try to retrieve the record it returns as null. I ...
18
votes
4answers
678 views

Is "CREATE INDEX` in MySQL a Linear Operation?

What I mean is the following: If creating an index on a table with n rows takes t time. Will creating an index on the same table with 1000*ntake approximately 1000*t time. What I'm trying to achieve ...
2
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2answers
800 views

Logical schema development and migration tool for different physical schema available including triggers and stored procedures?

We are planning to support for our application another rdbms (oracle). At the moment we are design our database schema with the MySQL-Workbench. For every new database version we have schema ...
8
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2answers
40k views

How to configure global charset on MySQL

I tried to change the charset for our MySQL via my.cnf and it failed. I added the charset settings listed below: # The MySQL server [mysqld] port = 3306 socket = ...
0
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1answer
1k views

MySQL Replication question

I have setup a master-slave replication between two MySQL servers using mysql Version 14.12 Distrib 5.0.51a, for debian-linux-gnu. Recently the replication errored out with this in the logs: ...
2
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1answer
816 views

mysql replication deadlock slave stopped

I've a master and slave and got the slave stopped with the following error log in slave. I want to fix this and get the two servers on synch and get going again. 111128 8:42:24 [Note] Slave I/O ...
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2answers
157 views

MySQL Records Turnover: How to do it?

I have a table of villas ordered by the UID as follow : UID, name, random_order: 4, villaA, 12 8, villaB, 5 9, villaC, 9 11, villaD, 2 I want to show my villas according to the random_order ...
3
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2answers
3k views

MySQL trigger: Compare value in another table

I have the following trigger (generated using PHP via mysqli)... DROP TRIGGER IF EXISTS post_queue_insert; CREATE TRIGGER post_queue_insert AFTER INSERT ON posts FOR EACH ROW BEGIN IF ...
1
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1answer
4k views

ERROR 1114 (HY000) at line 6308 in file & The table user_analysis is full

There is a SAN mounted 1TB partition for Mysql backups in our server with version 5.0.45-log. From two days, im seeing the log entries ERROR 1114 (HY000) at line 6308 in file & The table ...
5
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2answers
3k views

EXPLAIN output suggests that my index is not being used

I have set up my table with an index only on done_status(done_status = INT): When I use: EXPLAIN SELECT * FROM reminder WHERE done_status=2 I get this back: id select_type table type ...
6
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1answer
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Why mysql 5.5 slower than 5.1 (linux,using mysqlslap)

my.cnf (5.5 and 5.1 is the same) : back_log=200 max_connections=512 max_connect_errors=999999 key_buffer=512M max_allowed_packet=8M table_cache=512 sort_buffer=8M read_buffer_size=8M thread_cache=8 ...
3
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2answers
588 views

Monitoring InnoDB Index Utilization

I would like to monitor how many queries are utilizing the indexes. Is there any program that can show me live query performance and index utilization? Note: I am already aware of slow log file and ...
1
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1answer
195 views

Add info to mysql view around an IP address - 10.10.1.100 to https://10.10.1.100

I have built a database in MySQL to replace the use of MANY excel spreadsheets that document our servers, network, IP addresses, etc. In that database I have created a view called DRAC (dell remote ...