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

learn more… | top users | synonyms

1
vote
3answers
2k views

MySQL: Trying to update to 5.5

I've followed this instructions, but after mysqld --skip-grant-tables --user=mysql, I'm getting this: 110913 20:29:18 [Warning] Can't create test file /var/lib/mysql/my-laptop.lower-test 110913 ...
1
vote
4answers
79 views

How to backup live mysql database?

I have 12 GB MySQL InnoDB Database with around 800 queries per second. No sooner I start 'mysqldump' over it to make backup I start getting '503' on my website. How do I make backup of my live ...
1
vote
1answer
64 views

MySql - unique key not working

I have the following table: CREATE TABLE `timeline_lists` ( `id` int(11) NOT NULL AUTO_INCREMENT, `user_id` int(11) NOT NULL, `list_type` int(11) NOT NULL, `s_object_id` int(11) NOT NULL ...
1
vote
1answer
28 views

Is it possible to find the user whose aggregated score reaches X value first?

Given this sample fiddle containing sales value and date for two users: http://sqlfiddle.com/#!2/8148be/3 How can I find the first user who has reached a total saleValue of 30 since the beginning of ...
1
vote
3answers
134 views

Will redirecting queries to dev/null warm up indexes?

I'm trying to warm up the buffer pool. Will running a query and re-directing the output to /dev/null suffice? e.g. mysql -u username -p -e "select id from tbl where 1=1" > /tmp/results.txt Thanks
1
vote
2answers
51 views

Mysql Master Offline

In a unidirectional Master-Slave setup, should the slave be manually stopped in cases where the Master is offline due to Maintenance, Crash etc. ? Or should one just leave it so that it keeps trying ...
1
vote
1answer
866 views

column auto updated after 24 hours in mysql

i have a table T1 with column : Name State time mon 1 2014-01-09 11:23:00 tue 0 2014-01-07 14:40:00 wed 2 2014-01-08 09:23:00 thu ...
1
vote
1answer
7k views

Enabling LOAD DATA LOCAL INFILE in mysql

LOAD DATA LOCAL INFILE is not enabled by default. Normally, it should be enabled by placing local-infile=1 in my.cnf. But it does not work for all installations. In my experience, it worked for Debian ...
1
vote
3answers
984 views

Backup / Export data from MySQL 5.5 attachments table keeps failing!

Can anyone please help! - I have a large table in a MySQL 5.5 database. It is a table which holds a mixture of blobs/binary data and just data rows with links to file paths. It has just over a million ...
1
vote
2answers
927 views

Changing the mysql.proc table directly after upgrade

Our host upgraded our mysql install without us knowing from roughly 5.1 to 5.5. This caused a problem because the table definition of mysql.proc is different as discussed here: ...
1
vote
1answer
1k views

Is it possible to force drop of mysql tables with FK?

For dropping a table in which a Foreign Key is used in other tables, it is necessary to drop all other tables having FK connection with the corresponding table. Is there a short way to drop a table, ...
1
vote
1answer
51 views

How are these two user drops different?

Other than the obvious, what is the difference between: drop user user_01@host01; and drop user 'user_01'@'host01'; In a sample test, they both achieved the same result. From Account Names docs ...
1
vote
1answer
582 views

Change root password of mysql database

This could be a Rookie problem , but it seems that i am not able to solve it. I have MySQL server installed on my windows machine(MySQL 5.5) under the Admin username root. Some How i lost the ...
1
vote
1answer
638 views

when will Innodb support activation of triggers on cascade foreign key? [closed]

The Manual says: http://dev.mysql.com/doc/refman/5.6/en/innodb-restrictions.html Currently, cascaded foreign key actions do not activate triggers. Any Idea when will this be implemented. Is ...
1
vote
3answers
234 views

getting error while starting memecached service with ndb engine

i am installed memcached library by following the steps in the internet. now there is a binary file created in bin folder of mysql now i exicuting the command memcached i am getting error like this ...
1
vote
1answer
639 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
2answers
350 views

Difference between On Delete Cascade & On Update Cascade in mysql

I have two tables in MySQL database- parent, child. I'm trying to add foreign key references to my child table based on the parent table. Is there any significant difference between ON UPDATE CASCADE ...
1
vote
1answer
94 views

Is there a product to auto-build indexes based on slow queries?

I'm looking to either find, purchase, or write a script to identify slow queries, identify potential missing indexes, and when needed create the appropriate index within a reasonable amount of time of ...
1
vote
2answers
2k views

How to outer join multiple tables to retrieve uncommon records

I'm trying to do an outer join in MySQL to identify records not common to 3 tables. Here's my current effort http://sqlfiddle.com/#!2/02b92/30 I'm trying to retrieve the records not common to all ...
1
vote
2answers
59 views

Are relay logs necessary for replication?

I'm trying to understand when/where using relay log is beneficial. According the documentation, mysql captures and writes events from the master's binary log as the result of the I/O thread. Then, the ...
1
vote
2answers
136 views

Nested query efficiency in MySQL

I have a table with several attributes like this: id id2 attribute -------------------------------- 1 100 blue 2 100 red 3 100 green 4 100 white 5 102 blue 6 102 green 7 102 ...
1
vote
1answer
445 views

Mysql 5.5 InnoDB growing CPU - Going crazy

Good morning, I'm currently facing a problem where CPU usage keeps going up until the server crash. I've tried multiple best practices proposed in this forum and on Percona, reinstalled the server ...
1
vote
2answers
218 views

avoiding unique key collisions across tables

This might be related to the idea of data warehousing, but i'm not sure, though it is extreme theory. We have a table where records get written to first, let's call it tbl_recording which looks like: ...
1
vote
1answer
86 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 ...
1
vote
2answers
660 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 ...
1
vote
2answers
71 views

need help in Query optimization

I need help in query optimization,I am having table with structure Create Table: CREATE TABLE `ip_country_mapping` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `cron` bigint(20) NOT NULL, ...
1
vote
2answers
65 views

Need some support on MySQL Query

I have a query SELECT leads.id, sfav.id is_favorite FROM leads INNER JOIN teams tst ON tst.team_set_id = leads.team_set_id INNER JOIN members members ON tst.team_id = ...
1
vote
1answer
2k views

ERROR 13 (HY000) When Creating Database

I'm trying to create a database and when I type in CREATE DATABASE epik; I get the error ERROR 13 (HY000): Can't get stat of './epik' (Errcode: 13) I am running kubuntu 13.04 with mysql 5.5.31.
1
vote
2answers
317 views

How to avoid lagging when enabling log-slave-updates?

Master: 48GB RAM 16-core my.cnf: https://clbin.com/hlkUo Slave: 64GB RAM 24-core my.cnf: https://clbin.com/viLm0 Both are running 5.5.28. For the incremental backup purpose, I need to enable ...
1
vote
1answer
1k views

How to Log IP Address for Inbound Connections in MySQL

Is there a way in MySQL 5.5 (on Redhat 6.x) to log the IP address from where a particular query has been run? And have that appear in the general log or even relay and bin logs? I am trying to track ...
1
vote
1answer
684 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 ...
1
vote
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 ...
1
vote
1answer
267 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 ...
1
vote
2answers
172 views

Is there a way to get slow-query-log-like profiling information on a single query?

Specifically, I'm looking for this information: # Query_time: 0.011922 Lock_time: 0.000088 Rows_sent: 107 Rows_examined: 663 Rows_affected: 0 Rows_read: 107 # Bytes_sent: 4152 Tmp_tables: 3 ...
1
vote
1answer
677 views

How can I trigger this stored procedure on insert?

I have a table of error messages to which errors will be inserted. I also have a table defining interactions between errors. For example, when a "Power Restored" error occurs, it clears any previous ...
1
vote
1answer
25 views

Failing to get multiple values using join

I have below scenario: create table t1 (id int, title varchar(20), description varchar(20)); create table t2 (id int, info1 varchar(20), info2 varchar(20)); create table t3 (id1 int ...
1
vote
1answer
41 views

Simple query hangs on a specific column condition

I have two servers, and I a dumped the database of the first to restore it on the second. Everything works great, except that on the second server, I can't do any selection based on a specific column ...
1
vote
2answers
91 views

Monthly report by time [closed]

I work in a parking company. We need a report of monthly vehicle exits by time. select hour(datetimeout) as 'dateout',count(*) from to_leaveveh where datetimeout between '2014-09-01' and ...
1
vote
2answers
158 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 ...
1
vote
1answer
133 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 ...
1
vote
2answers
56 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 ...
1
vote
3answers
192 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
159 views

unable to import the file

Gone through the below link also but i am unable to import CSV file in mysql. Even i had tried by using > LOAD DATA LOCAL INFILE but same error persisting. Please help me in this. queries i tried had ...
1
vote
2answers
100 views

getting one day timestamp in mysql

Please consider the following stored procedure I have: ORIGINAL Stored Procedure: -- -------------------------------------------------------------------------------- -- Routine DDL -- Note: comments ...
1
vote
1answer
131 views

Safely changing innodb_buffer_pool_size on MySQL replication master?

We have a MySQL server which is a replication master. We need to change the innodb_buffer_pool_size and innodb_flush_method to (hopefully) improve performance as the database has grown. What is the ...
1
vote
1answer
120 views

database design for dynamic menu bar [closed]

I am trying to create a menu bar which will load dynamically on user log in, based on the user roles. Say if the user is an admin he can see all the items listed under the header and if a user is a ...
1
vote
1answer
74 views

Migrating MyISAM tables from 5.5 => 5.6

I was wondering if anyone had any pointers on migrating MyIASM tables from mysql 5.5 to 5.6, specifically using Percona builds, via an rsync? Is this safe? I know we need to do a full ...
1
vote
1answer
102 views

How to store temp tables in memory during table “optimize”?

When optimizing tables, SHOW PROCESSLIST lists it as "copying to tmp table". I'm trying to ensure the copy takes place in memory to speed up the process. I've tried adjusting the tmp_table_size to ...
1
vote
1answer
98 views

What is the difference between uniqe index/unique/unique key/unique constraint keywords?

I am using mysql 5.5.16 What is the difference between the following DDL statements? 1) create table sql_query ( id int not null , query_text varchar(21826) not null , query_md5 ...
1
vote
2answers
112 views

Indexes slowing Insertions(Can't use Explain Insert to Analyse)

I have a MySQL database, I am parsing files from a log and inputting it inside. So far including a simple 4MB file in the database could take me about 4 minutes to insert ! and i have about 10,000 ...