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

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0
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2answers
9 views

Using MySQL/PHP PDO, is there a 'simulate' or dry run option?

Does MySQL (or, ideally, PHP PDO) have some way of simulating transactions without actually committing them? (Can I get MySQL or PDO to act as if data is inserted/deleted/updated, without actually ...
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0answers
23 views

Too much IO to MySQL InnoDB log files

I am using MySQL version: 5.5.38 I have dedicated HDD to InnoDB log files using innodb-log-group-home-dir option. atopsar -d 30 shows big load (>50%) to this HDD The thing is that I have only 75 ...
3
votes
2answers
268 views

MySQL runs out of memory when importing innodb database

I have a small VPS with 512MB RAM and no swap (can't have any). I am importing a 1.5GB innodb database with mysql -u -p < database.sql Before the operation can finish it says : Lost connection ...
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0answers
4 views

pt-online-schema-change with circular replication

So I have an alter table (adding 4 columns) to do on a fairly large table (74 million rows). The problem is this table has firstly to remain online and writable during the whole operation and ...
0
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0answers
7 views

Why pages not made young is zero?

In results of Show INNODB Status showed me very weird result: Pages made young 81821279, not young 0 The official statement says: Pages made young, not young: The number of old pages that were ...
0
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0answers
10 views

Change MAMP to use a lower Mysql 5.1 version

I need to have the same development environment for my PHP program. My clients test server is running on Mysql 5.1 while my local is using MAMP running Mysql 5.5. How do downgrade my mysql database ...
2
votes
2answers
74 views

How to generate auto increment values for my duplicate column in my sql?

How to display when i was run to find duplicate values from my table at this time i want to add new column in select statement with auto increment values SELECT * FROM tutorials_tbl WHERE Lscno IN ...
0
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2answers
34 views

How to resolve: Specified key was too long; max key length is 767 bytes [duplicate]

Our server is creating a lot of tables and one of them is the Lock_ table. We are using MySQL 5.5 on Percona. Also we are using utf8_general_ci and utf8. It throws the following error when creating ...
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1answer
204 views

Mysql query is very slow

I am developing a website like any other social networking site using mysql. I wish it give people suggestion to my users, and I have implemented this functionality in my application, but It is ...
0
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2answers
45 views

Mysql replication from existing slave to new slave

I'm hoping you experts can help advise me, I've got this topology: Live DB(Master) ----> Backup Server (Master and slave) ----> Test DB Backup server is a slave of Live DB, and Test DB is a slave of ...
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1answer
38 views

Is there any limit for MySQL database rows

I'm creating a database website which has a lot of data (Username,name,address,posts etc). Is there any limit to store database rows? (I have a table with more than 100,000 rows) How to host this ...
0
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1answer
34 views

What is wrong with this statement? 'Unknown column'? [duplicate]

I'm not used to the 'as' keyword and I thought it would be a nice idea to use it. So why do I get an 'unknown column' (eid) error? I use mysql... select t1.index as eid, t1.col1 as col1, t1.col2 as ...
2
votes
1answer
186 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 ...
0
votes
1answer
24 views

Add database to existing replication which uses binlog_do_db?

We have two MySQL 5.5 servers running on Ubuntu 12.04. We are successfully replicating 3 databases from server01 to server02, but need to add a 4th (new) database. Our my.cnf on the master has: ...
1
vote
1answer
45 views

Group by age range and gender with aggregation function on some columns

In Mysql, I have a patient table with id, birth_year and gender. Next table is transactions in which I have id, patient_id [FK from patient] and checkup_date. I need to select rows such that I get ...
0
votes
1answer
23 views

MySQL service failed to start “mysql.sock seems missing” WAMP Server acting up

WAMP server on my machine is failed to start MySQL services. Few minutes back it was working fine. I tried to change the configuration of MySQL with the help of my-huge.ini file (just renamed this ...
0
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0answers
12 views

Soundex on a Large Table

I had a table of names, containing 200,000 rows. This has now been updated to include over 11 million rows. The table is queried using a SOUNDS LIKE 'str' and the result is then passed through ...
3
votes
2answers
1k views

MySQL information_schema doesn't update

I have a database, say abc, in mysql server. It has only one table named test. test uses innodb engine and I've set innodb_file_per_table to true. After I run the query delete from abc.test, I want ...
0
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0answers
16 views

Unaccounted for MySQL Processes

I am running a MySQL 5.5.38 on a VM running Ubuntu server 12.04. At certain times of the day around 12 mid day, CPU Utilization and loads spikes to over 90% with the MySQLD Process accounting for most ...
3
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2answers
42 views

Is this substring_index behaviour documented or a bug?

mysql> show variables like 'version'; +---------------+-------------------------+ | Variable_name | Value | +---------------+-------------------------+ | version | ...
0
votes
1answer
81 views

mysqldump 5.5.25 use swap instead of memory

mysql version 5.5.25, while use mysqldump to dump big tables, it eat lots of swap while there is lots of free memory. # free -m total used free shared buffers ...
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0answers
40 views

SUM function with nested query in mysql [on hold]

I need to use the sum function to join one other table of my results.but this query gives wrong results. SELECT table1.id,titletable.title,table1.s,table1.parentid FROM ( SELECT mt1.id ...
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1answer
16 views

Importing Data with Single .ibd file

I have one ".ibd" file with me. I have configured my local Database server with FILE_PER_TABLE option. i have two question here. When i was trying to restore/import the IBD file, the engine expect ...
0
votes
1answer
325 views

Strange Locking issues while playing back logs via percona playback

Problem while replaying logs I am in the process of benchmarking a new DB node (specs at the end) and have run across some strange behavior: As described here i: Created a dump (innobackupex ftw) ...
0
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2answers
104 views

Uninstalling MySQL on Solaris

I have installed MySQL 5.5.31 in Opensolaris. When I tried starting the MySQL server, it says bash: mysql: command not found So, I decided to uninstall the whole lot and try doing again. But I could ...
0
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2answers
54 views

query execution time in mysql

I have run the query in mysql which consists of approximately 33million records when i have executed the query select population1 < 200000 from city; it shows like this after execution ...
1
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3answers
73 views

How to get “mysqlbinlog” utility for Ubuntu?

I can't find "mysqlbinlog" utility in my Ubuntu server, i can see mysql, mysqldump, mysqlshow etc... command line utilities but not mysqlbinlog utility. Can someone please help me from where I can ...
1
vote
1answer
68 views

Installing MySQL in Solaris

I am trying to install MySQL 5.5 on Solaris 10. I executed the code useradd -r -g mysql mysql where a group called mysql is already created using groupadd command. I get the following error : UX: ...
0
votes
1answer
23 views

MySQL my.cnf: innodb_log_file_size is missing

How to set innodb_log_file_size to MySQL database if there is no innodb_log_file_size in my.cnf configuration file? I'd like to backup via Percona Xtrabackup and the backup crashes at this point ...
0
votes
2answers
57 views

Mysql 5.5.25 must be restarted to connect

We have MySQL v5.5.25 running on Windows Server 2008 R2. Occasionally people are unable to connect, and the only way we have found to fix this is to restart the mysql service. This happens every 2-3 ...
0
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0answers
28 views

Mysql server stops responding quickly after +- 200 connections

We have a mysql instance, 5.5.28. Its working as intended, it has during normal operations perhaps around 200 to 300 connections on it. These connections are usually "idle" waiting for something to ...
0
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0answers
20 views

(libmysql): (filename not available): mysql_query

Hi everybody im running a game server connected to mysql and it crashes only because of mysql connection with the error in title.. when i dont use mysql and save data as files on harddrive it dont ...
2
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2answers
48 views

How do you update a large MySQL table that's on a server?

I have an application on a web server. The PHP front end for the application queries a MySQL database which has a table that contains 60 million taken domain names. My application queries this ...
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vote
2answers
37 views

MySQL: How to sync on demand beetwen two database in the same server

I'll like to know if it's possible to have a systeme on synchronisation beetween two database in the same server. I have a production database in my server , i want a dev database (same database with ...
4
votes
2answers
93 views

Query only for the first n results of like

What I'm trying to accomplish is a huge speedup (read: incremental results) when searching a database with a like operator which is kind of a last resort, if everything else already failed, to come up ...
3
votes
2answers
147 views

Problem in Fetching Result set in Desired Format

I have 2 tables having the following columns Person ------ person_id, first_name, middle_name, last_name Items ----- person_item_id, person_id, item_type, status, ordered_date The query is ...
0
votes
1answer
57 views

Slow INSERT/UPDATE on InnoDB

I have a problem with the performance of my MySQL server, let me explain: I instaled a MySQL server, version 5.5.20 Server version: 5.5.20-log Source distribution SELECT queries runs fast on ...
2
votes
0answers
35 views

Emulating WITH clause in MySQL/query perfomance review

I have never really worked with MySQL queries till this last week. I was tasked with making a simple tool for my department that tracks contacts. Here are the 2 tables and the type of data they ...
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2answers
43 views

MySQL user without SUPER privilege

This may be a simple question and may not be the right place to ask but I couldn't find any useful information from Google. Here is my question. When creating users in mysql using grant all ...
0
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1answer
147 views

Unable to run update_mysql in MySQL 5.5

I have recently taken over managing a MySQL database running on Windows Server 2008 R2 . It is running 5.5.37 Community Edition. When it is started, it includes the following lines: Thread, Type, ...
1
vote
1answer
288 views

Two different MYSQl instances on same machine?

I have MySQL 5.6 installed (Linux). /var/lib/mysql /etc/my.cnf I have a cold backup that I am recovering: /var/lib/mysql_backup /etc/mybackup.cnf In April I was able to get the backup started ...
0
votes
1answer
171 views

Restrict access to rows by usename

In my database i store data of different users (e.g. addresses or invoices) in the corresponding tables. I want to make sure that a logged in user only has access to it's own data in the tables (so ...
0
votes
1answer
96 views

Whether to use or not to use: DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP

In one Database table, created_at & updated_at are defined as: `created_at` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP `updated_at` timestamp NOT NULL DEFAULT ...
0
votes
1answer
30 views

Simple Query optimization using ORDER BY

The following is a simple query that is taking more than 10 seconds to execute: select * from inventory.asset ass where ass.product_id=83 and ass.expiry_date > now() and ass.status=1 order by ...
3
votes
1answer
126 views

MySQL RDS Instance eating up memory and swapping

I have an issue with memory on a RDS instance which is of db.m2.4xlarge class. Below are the specifications of the RDS instance Instance Class: db.m2.4xlarge ( 68.4 GB of RAM ) Engine: ...
3
votes
3answers
316 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 ...
0
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1answer
164 views

Data Analysis with MongoDB or MySQL

I have a need for processing some data in order to come up with some statistic. This is the scenario: Each user can answer several questions from the question list. They pick their answers from a ...
0
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1answer
76 views

Mysql improve Self join performance large table?

I have a task to help identify conflicting IP ranges , I want to highlight when one companies IP range falls within another's ... below is the sample table, I have converted the IP ranges from .dot ...
0
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1answer
40 views

MySQL JDBC does not behaves as the MySQL Workbench

I'm running the following from the MySQL Workbench, and from my local tomcat using jdbc. START TRANSACTION; CREATE SCHEMA IF NOT EXISTS `ROOT`; CREATE TABLE IF NOT EXISTS `ROOT`.`all_tables` ( ...
0
votes
2answers
91 views

Database Design Help: MySql/PostgreSQL Single Database/Multiple Databases

We are planning to build a web based custom business analytics tool using PHP and MySQL/PostgreSQL. In our application, we are planning to upload customer’s data using a Excel sheet and these data ...