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

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2
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1answer
31 views

Is there an easy way to update a mysqldump file from version 9.11 to 10.11? [closed]

We have a client that has had their servers for soo long, they were still running MySQL 4.0.24. Now that they are refreshing their servers, we took a mysqldump of their current database to put into ...
1
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2answers
365 views

DELIMITER issue in MySQL 5.6

Drop procedure if EXISTS rotatepjp; DELIMITER // CREATE PROCEDURE rotatepjp() BEGIN DECLARE u_id, settingval, pjp_userid, pjp_beatid, u_frequency INT; DECLARE u_pjpstartdate, pjp_fordate, ...
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3answers
7k 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 ...
0
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0answers
63 views

ERROR 1644 (HY000) at line 1852: Unexpected content found in the performance_schema database

I was upgrading MySQL from 5.1 to MySQL 5.6 on a Linux server installed with RHEL6. I already have 5.1 installed and running with about 300GB of database data, so I want to do a in-place upgrade to ...
1
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2answers
48 views

Why is restoration from binary logs so slow?

We have a MySQL 5.5 server with binary logging enabled and a backup script that collects the binary logs and, once a day, generates a complete database dump with mysqldump. In testing database ...
1
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2answers
120 views

Mysql causing high load average with large amount of server resources left

I've have 2 servers running a application and the server that runs the mysql sgbd is with the load average around 3 times more than the webserver. I think that is something wrong because i have a lot ...
1
vote
1answer
38 views

MySQL, can't find MYD files on OS X, MAMP

Try as I may I can't find the data files for my MAMP installation! FRM files are here: /Applications/MAMP/db/mysql/database_name/ but, there are no corresponding MYD or MYI files anywhere. The ...
1
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1answer
35 views

In slow_log tables, sql_text column showing “throttle: index not used' warning(s) suppressed” instead of exact query

I'm trying to find the slow running queries from slow_log table (as I don't have direct access to server to check slow log file). In sql_text column instead of query it is showing "throttle: index not ...
1
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2answers
62 views

Awful execution plans after migrating from MySQL 5.5.11 to MariaDB 5.5.41

We just migrated our web site database from a server running MySQL 5.5.11 to one running MariaDB 5.5.41. Everything is working mostly fine, except there's at least one query from our storefront that's ...
0
votes
1answer
69 views

'USE db_name' takes too long to change when login remotely

I gave SELECT privilege to a user on a particular database, Now whenever I try to connect remotely $ mysql -h ip-of-remote -u username -p with that user credentials and try to change the database ...
0
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0answers
94 views

how can i connect from yahoo small business webhosting domain to remote mysql server

so far I have done these: set up remote access using Remote Mysql.Added the yahoo website's domain ip and yahoo nameservers. went on to my website on yahoo small business and set up an Aname and ...
1
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2answers
356 views

grant select on all databases except one mysql

I have user called test_user created under MySQL 5.5.17 under MS Windows 2008R2, I want to grant this user select privileges on all databases except MySQL database, note I have around 200 database ...
1
vote
0answers
31 views

Unsafe statement written to the binary log using statement format

In MySQL error log I am getting this warning message: [Warning] Unsafe statement written to the binary log using statement format since BINLOG_FORMAT = STATEMENT. Statement is unsafe because it ...
5
votes
1answer
138 views

MySQL overhead of calling a Stored Procedure

Within Java, we access MySQL (v5.5.40) via JDBC -- a prepare statement, setting parameters then calling the stored procedure. It appears that every execute() has the overhead of 4 meta-calls (per ...
7
votes
2answers
916 views

Why are mysql password hashes internally saved with a star (asterisk)?

I was reading upon some mysql internals, when going through the mysql.user table in the my mysql shell, I get mysql> select * from mysql.user limit 1 \G *************************** 1. row ...
0
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2answers
67 views

How to most efficiently store possible combinations of categories?

I have a table of categories (currently with 14 rows, not likely to change). A need to cache combinations of categories emerged, so I'm creating a table of allowed combinations (only few hundreds of ...
1
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0answers
21 views

How to make an indexed search over a list (set)?

A follow-up question for How to most efficiently store possible combinations of categories? An answer pointed to SET datatype. As far as I know, the default search option for it, FIND_IN_SET, doesn't ...
0
votes
1answer
25 views

manual transfer fails with table does not exist

I performed a manual transfer of data manually (zip up the dir and rsync'ed it over. I moved the members.ibd (the only .ibd file) to a save place, extracted and then replaced members.ibd with the ...
0
votes
1answer
64 views

Error: Incorrect usage of UNION and ORDER BY

I have this query: SELECT DISTINCT CONCAT (MONTH(`Date`),'-',YEAR(`Date`)) from wp_result_plugin WHERE Bet=2 AND month(`Date`) = EXTRACT(month FROM (NOW())) ORDER BY MONTH(`Date`) ASC UNION ...
0
votes
1answer
15 views

Import lots of mysqldumps with missing CREATE DATABASE

I have a bunch of mysqldumps of my old server with one database each. Unfortunately we forgot to add CREATE DATABASE ... in all those dumps. How can I import those files in one batch?
0
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2answers
991 views

SQL Query is sometimes slow, sometimes fast

I have two hosts, one with my rails app, one with my MySQL database. Going through my rails Logfile I can see that sometimes queries take much more time than the same query at other times. Think 200ms ...
0
votes
1answer
90 views

mysql database under symlinked directory: ERROR 1018 (HY000): Can't read dir of './<dbname>/' (errno: 13)

I'm using mysql 5.5 on an ubuntu linux server. I need to move a database from its current location (under /var/lib/mysql) to a disk with more space, so I attempted to move the directory and create a ...
0
votes
1answer
21 views

Can combine five mysql statements into just one statement?

Can I combine all the five statements into just one statement? update mytable set myfield1 = replace(myfield1, '…' ,'-') ; update mytable set myfield1 = replace(myfield1, '‖' ,'|') ; update mytable ...
0
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0answers
36 views

IF statement inside stored procedure, seems to cause locks by side effects

We are running a MySQL 5.5. server with READ-COMMITTED transaction level to store and process a large time series dataset. We have a large time-series-table, into which we write batch updates every ...
3
votes
2answers
11k views

MySQL Error Reading Communication Packets

In MySQL error logs, I see these quite few a warnings like these: 120611 16:12:30 [Warning] Aborted connection 2619503 to db: 'db_name' user: 'user_name' host: 'webapp_hostname' (Got an error reading ...
0
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0answers
19 views

Optimizing MySQL for write throughput ceiling

We have a large MySQL database on AWS RDS, with a huge table around ~1.8TB with massive write workload. We recently hit a write throughput bottleneck, which caps our provisioned IOPS way below the ...
0
votes
0answers
13 views

creating best results from two tables

I have two tables, one is the results of an assessment from users(per row) and column starting with 819....X1 represents the qid. The other table holds the score for the answers (A1,A2,A3), both are ...
0
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0answers
55 views

Tunning MySQL Variables

we have a dedicated mysql server with 10 CPU and 32G of memory After doing some readings came up with those configs : # This was formally known as [safe_mysqld]. Both versions are currently parsed. ...
1
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1answer
6k views

Error 1044 Access denied to user

This is driving me crazy. When I try to create a few tables from my Workbench model I get this error 1044. I've been trying to find a solution but nothing works for me. Curiously when I run ...
0
votes
2answers
55 views

Get rows where lastLoginTimestamp is in last 7 days

I'm trying to get the rows from a table where lastLoginTimestamp is in last 7 days and I'm doing as follow: SELECT * FROM representative WHERE DATE_SUB(lastLoginTimestamp, INTERVAL 7 DAY) ...
1
vote
1answer
63 views

phpMyAdmin and mysql not showing the same database

I have setup WAMP which I managed by using a tutorial and everything seems fine... I am logging into mysql as the root user with full privileges granted and I am able to create databases in mysql and ...
0
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1answer
58 views

MySQL Crash After Starting Binary Logs

Recently I have added binary logs to mysql to start replication but after that setting, mysql process failed to start and keep crashing constantly. In mysql error logs some messages are there but not ...
1
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2answers
745 views

MySQL - grant all privileges on *.* brings back Access denied

GRANT ALL PRIVILEGES ON *.* TO 'username'@'localhost' IDENTIFIED BY 'somepassword'; Brings back error : ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES) If ...
0
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0answers
37 views

Daemon Waiting for activation in mysql event

When I do, SHOW PROCESSLIST; on mysql, for my event, I see the following result: Q1 )Why does it shows Waiting for next activation all the time? Q2) At times my scheduler turns off which causes my ...
0
votes
1answer
37 views

Unable to get the latest value added to Mysql table based on posted time

SELECT * FROM discussion_comments GROUP BY disc_id ORDER BY posted_date DESC I have table example like given below: CREATE TABLE example ( id int(11), cname varchar(11), posted_date date, ...
0
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0answers
50 views

MySQL is pretty slow after 50-100k rows whats happen?

i have trying now a lots of time, and i try to find a way there make sense to find out of my problem, but this problem stil make a lot perfumes issues. i testing it of on a developer server ( 2 ...
1
vote
1answer
31 views

Installed Percona-Toolkit, but no sign of xtrabackup

I've installed Percona-Toolkit on my Debian (Wheezy) test Server, using dpkg -i percona-toolkit.deb apt-get install --fix-missing -f dpkg -i percona-toolkit.deb However, there is no sign of ...
0
votes
1answer
36 views

“show procedure status” displaying the non existing databases stored procedures in mysql server

i have taken a mysql server backup using mysqldump and imported the backup file in another mysql server.Import failed because of disk full issue. Only 11 databases are created out of 15 . when i issue ...
0
votes
1answer
42 views

No records in Mysql.func table even though there are stored functions in server

When i am creating a user defined function in one of my mysql server, it's not creating any row in mysql.func table . Even though i have multiple functions in my mysql server , this table is empty . ...
2
votes
1answer
1k views

Space not reclaimed after dropping MyISAM table

I just dropped a rather large MyISAM table (~4 gb); it was 350k rows with about 11k of data per row. However, when I run df -h on my database server, I am still at 100% disk usage, so much so that I ...
0
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0answers
19 views

How to create relations in database

I have two table: users and projects. In projects admin can add projects like: web design, SEO , etc.... I need to add abilty to admin can add some users to certain project... For example I need ...
0
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0answers
43 views

Mysql Trigger to call a java method, its pros and cons?

I have a requirement to call a Java method once a new record has been inserted in to the DB. I would like to know is it a efficient way to do ? what could be the performance issues as my table expects ...
1
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1answer
40 views

Warehouse Database Design Question

Apologies if this has been answered previously but I have been unable to get a specific model to work. I have a database table that needs to store some very basic info for a reporting system. The ...
1
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3answers
4k views

MySQL Table not repairing

Table info: Database name: user_motiva Table name: wp_options.frm wp_options.MYD wp_options.MYI wp_options.TMD when I do a mysqlcheck -r --all-databases it gets hung on that table even if you ...
5
votes
2answers
28k views

ALTER TABLE - Rename a column

This got me nuts! I want to rename a column from read-more to read_more in blog table Tried all this: ALTER TABLE blog RENAME COLUMN read-more to read_more; ALTER TABLE blog CHANGE COLUMN ...
1
vote
1answer
134 views

How to turn Event Scheduler On permenantly in mysql

How do i turn on the event scheduler in mysql permanently. I'm using phpmyadmin and i have scheduled an event to copy records from one table to another everyday at a specific time, but the records are ...
0
votes
1answer
104 views

MySQL: How to write a recursive function to show menu tree?

I try to build a menu tree inside the SQL with this function: DROP FUNCTION IF EXISTS hello_world; DELIMITER $$ CREATE FUNCTION hello_world(_typeId INT, _typeText TEXT) RETURNS TEXT BEGIN ...
0
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0answers
17 views

MySQL 5.5 only use 1 thread and 30% cpu

i have a big issue, every day i need to update or insert like 3.3 milion rows, i have trying to do what ever i can but it still only run like 605 query/s i use VirtualBox so my setup are testing on 1, ...
0
votes
1answer
71 views

mySQL running on 100% CPU both on RDS and EC2

How do we troubleshoot an issue with Amazon wherein my database queries (PHP/MySQL) are eating 100% CPU most of the day? Traffic=200 connections average mySQL version = 5.5.40 The ...
2
votes
1answer
292 views

mysqldump doesn't restore database. why not?

Why doesn't my restore operation work? I created a dumpfile for a database using: mysqldump -u root -p databasename > /home/databasename_bkup.sql I then opened the dumfile and confirmed ...