All versions of MySQL (not Microsoft SQL Server). Please also add a version-specific tag like mysql-5.7 if that is relevant to the question.

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1answer
2k views

Trigger not working, why? [closed]

What i'm doing wrong? CREATE TRIGGER `Calc` AFTER INSERT on `test`.`bookings` FOR EACH ROW BEGIN UPDATE `test`.`article` AS `ST` SET `ST`.`stock` = SUM(`test`.`bookings`.`amount`) WHERE ...
0
votes
2answers
114 views

MySQL using swap during conversion to InnoDB

I'm trying to convert some MyISAM tables in my database to InnoDB (MySQL 5.1). The server has quite a bit of memory (96G), and the tables that are giving me problems can be on the order of 50 millions ...
1
vote
1answer
162 views

MySQL-test suite not included with windows mysql installer?

I noticed in my MySQL folder there is no mysql-test. Why is that? Is it possible to add it?
0
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1answer
128 views

How write mysql query corresponding this tables

This is my database tables I want to get this result: How can I write select query to get that result?
0
votes
1answer
557 views

Unable to take backup of mysql database using Xtrabackup

I am trying to take mysql backup without any downtime but unable to take the backup using Xtrabackup . Actual Database is almost about 40+ GB in size. I am trying to first satisfy myself. Hence, I ...
1
vote
0answers
494 views

MySQL, query optimization with join on huge table

I'm trying to execute a query on MySQL (Database created from a GTFS schema) I have two tables like these: trips trip_id | route_id --------------------- 1 | 409 2 | 409 3 ...
1
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2answers
2k views

Setting default CHARSET and DB Engine

I recently updated my server's database system from MySQL to MariaDB. After update, everything works well. But, when I went to phpMyAdmin, the default charset and types are changed: At the end of ...
0
votes
2answers
196 views

updating values in one table if depending table row is affected

there are two tables structure is like: product_table item_id product_id count_subscriber 1 2 4 2 3 5 subscriber_table item_id subscriber_id product_id 1 ...
5
votes
2answers
9k views

What is the meaning of tinyint(N)?

When we use an argument length with numerical data types, as far as I know this specifies the display width. I tried the following: mysql> create table boolean_test (var1 boolean, var2 tinyint); ...
1
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1answer
3k views

MySQL Service is not starting on linux

I am having a problem with my database it does not want to start :( the server is running on linux centos 6.2 it was working until I emptied the logs I don't know if this have anything to do with ...
1
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2answers
10k views

MySQL Update Trigger that updates multiple columns from values in another table

I have a table PRODUCTS with columns id, name, sku, packaging_type, width, height, weight, case_count. I want a trigger to fire when packaging_type is updated. packaging_type will be an integer ...
2
votes
1answer
774 views

How to UPDATE a column by COUNT of FK from another table?

How to extend this query for the entire table, to update all ids? UPDATE table1 SET number=( SELECT COUNT(*) FROM table2 where id=1 ) WHERE id=1 id is the PRIMARY KEY in table1 and FK in table2. ...
0
votes
1answer
2k views

Move data from one table to another

How do I retrieve data from one MySQL table and store the data into another database table on the same server. I have tried this code but keep getting errors: CREATE PROCEDURE `ProfusionTest` () ...
5
votes
3answers
2k views

CPU usage on RDS instance monotonically increasing with no change to query volume

I have two RDS instances: a R/W master and a read-only replica. On 29th June, the replica stopped registering replication data - not sure if this is related. On July 3rd, the master's CPU usage ...
3
votes
1answer
5k views

Putting a Select statement in a transaction

What is the difference between these 2 queries: start transaction; select * From orders Where id=1; UPDATE orders SET username="John" Where id=1; commit; And without transaction: select * From ...
1
vote
1answer
8k views

Stored Procedure Performance using Temporary Tables

I have the following Stored Procedure I would like to improve the performance of DELIMITER $$ CREATE PROCEDURE NEXT_UNIT_OF_WORK ( IN batchId INT, IN size INT ) BEGIN start transaction; ...
0
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1answer
94 views

Tracking changes on a replication slave

I suspect the answer to this is "you're boned", but I'd like to see if there are any good options that I haven't explored. We're building a system that will integrate with a 3rd-party POS system and ...
1
vote
2answers
7k views

MySQL Installation error: Unable to update security settings

I tried to configure MySQL server 5.5 on Windows and this is what I get mysql-server-5.5-winx64:56 - Attempting to update security settings. mysql-server-5.5-winx64:100 - Unable to update security ...
3
votes
1answer
1k views

How to modify `proxies_priv` in MySQL

I recently received a warning from MySQL that stated: [Warning] 'proxies_priv' entry '@ root@serverdomain' ignored in --skip-name-resolve mode. I looked in mysql.proxies_priv and there is ...
1
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2answers
111 views

Strange issue regarding my.cnf

I'm getting a weird message from phpmyadmin saying: #2006 - MySQL server has gone away What I found online is that I should increase the size of max_allowed_packet witch should be in the my.conf ...
2
votes
1answer
36 views

Automating MySQL DB Creation with Specific date

Here i come again with another challenge . Basically i'm looking forward for the best way to have a windows based script to create a MySQLDB, or multiple MySQLDB, once a week having the following ...
1
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1answer
97 views

Group by and average from related tables

Ok so this is kinda weird I'm not sure how to exactly tackle it without it being a massive query, that might be slow so this is the tables as it is Concerts: name | country_id | ticket_price foo 2 ...
1
vote
0answers
356 views

InnoDB: error: space object of table

131212 10:35:18 InnoDB: error: space object of table 'main/wp_m_membership_levels', InnoDB: space id 119 did not exist in memory. Retrying an open. 131212 10:35:18 InnoDB: error: space object of ...
0
votes
3answers
322 views

Large database - too much time spent opening and closing tables

I have a MySQL server (5.5.31) with 450 databases of some 200 tables each. (Yes, 90,000 tables) When we're under high load, there's over 100 concurrent queries, of which 70% are either opening or ...
1
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0answers
297 views

MySQL Link to PHPMyAdmin/MS Access

I have a mysql database stored on a server via phpmyadmin. I want to link this to MS Access for other users. I often link mysql databases to MS Access which are stored locally, but never DB's stored ...
0
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1answer
67 views

How to give a client backups of their data without compromising our database design? [closed]

The client is asking for backups of their data, however we would not like to share our database design as it may lead to a security risk... inb4: Security by Obscurity is not a valid security control ...
0
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0answers
203 views

Making cloned copies of a innoDB mySQL database

I'm trying to find a better way to clone innodb mysql database then using regular import. We use an innoDB mySQL database in production. A backup is created daily from production. Currently each ...
0
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0answers
162 views

Inserting and updating on same table

I am currently working on a database that aims to provide information regarding the amount of time people stay in a company's car-park premises. This is done using a table called "tbl_stay" which has ...
1
vote
2answers
149 views

Creating a mysql trigger without hard-coding database name

Is there a way to create a trigger in mysql without hardcoding the database name? Doing a typical create trigger will stop working if I dump the database and then import it into a database of a ...
1
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2answers
182 views

What is a mysqld process in a MySQL cluster?

As I know, a mysqld process is a kind of a router of a MySQl cluster. It directs requests to the right ndbd node. Assuming I have 3 ndbd nodes on 3 different machines and I don't use replication. How ...
2
votes
1answer
662 views

MySQL backup InnoDB

I have a VoIP server running 24x7. At low peak hour at lease 150+ users are connected. My server has MySQL running with InnoDB engine on Windows 2008 platform. I like to take at least 2 times full ...
1
vote
1answer
70 views

Is it more efficient to store 0 and 1 for a binary value or just empty and 1 in MySQL

Is it more efficient to store 0 and 1 for a binary value indicating whether a flag is up or down or just empty and then set 1 for rows where the flag is up. Using MySQL. E.g. Flag 0 1 1 0 0 Or ...
1
vote
1answer
264 views

Upgrading MySQL 5.1 to 5.5 - All tables gone [closed]

I'm trying to upgrade from MySQL 5.1 to MySQL 5.5. I followed the instructions here: http://dev.mysql.com/doc/refman/5.5/en/windows-upgrading.html I also adjusted the Datadir. But after the upgrade, ...
0
votes
1answer
183 views

MySql One-to-zero to one-to-one

I have a table Persons with id as pk and auto increment. Then I have a table Addresses with id as pk and fk to the Persons id. But now person can exist without an address, and I don't want a person to ...
0
votes
0answers
199 views

Error adding constraint foreign key to bridge table

Hi there I am fairly new to sql development. I am current following the head first into mysql book and is on chapter 6. On chapter 6 there is a table in third normal form but it does not contains the ...
2
votes
2answers
360 views

How to store logs correctly?

(This is somewhat a follow up on my last question) I am using MySQL 5.5 with innodb. My Log table consists of two columns. One for user number, and the other for a string consisting of IP, request ...
1
vote
2answers
1k views

MySQL query log

I wonder if there is an alternative for MySQL general query log. I would like to log (mostly) DDL statements, so I could trace what user DROP database/table etc. I know that enabling general query log ...
2
votes
1answer
1k views

mysql innodb space x did not exist in memory

Into my innodb log I got the errors below. How to fix? What did it mean? Some tables are corrupted but not all. InnoDB: space id 1753 did not exist in memory. Retrying an open. 130906 16:31:27 ...
0
votes
1answer
215 views

Looking for suggestions to Migrate Amazon RDS Large Instance to non-amazon host - Live

We have an Amazon RDS Large instance with a database of about 20GB that needs to be migrated without having to take our website down or minimize downtime to less than a couple of hours. And I am ...
1
vote
1answer
2k views

MySQL Regex matching newline or end of string

I have a text column in mysql which contains some values separated by a newline. I want now to query by these values and thought a regex should help me with that by doing something like: SELECT * ...
1
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0answers
54 views

Find the neighbouring polygons of a given polygon in a MySQL spatial table in ver < 5.6.1

Finding neighbouring shapes in MySQL spatial table made up of ID and 2D geometry (polygon) fields. I have a table with an ID column and a geometry column (holding a polygon) representing various ...
0
votes
1answer
292 views

Does size of one particular column in a database affect query performance?

I have a table user_list CREATE TABLE IF NOT EXISTS `user_list` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `username` varchar(40) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, `email` ...
1
vote
1answer
2k views

Mysql Performance tuning for myisam tables.

Folks I have a 4-core MySQL server with 4 GB of RAM, holding 19 MyISAM tables (total: ~164GB of data) and 32 innodb tables ( 5mb ) and we use it to process CDR files( basically call detail records ...
0
votes
0answers
576 views

Queries get stuck for no obvious reason

We have magento running with MySQL. We're getting problems where queries would take much more time to execute than they should. In example: INSERT INTO `catalogsearch_result` SELECT 63 AS ...
1
vote
0answers
174 views

Most efficient way to sort data fields into SQL

I'm trying to decide on the most efficient way to sort various data values. Here's how the data arrives: Device X sends a text string "name=value&name2=value&name=value" On arrival that ...
5
votes
1answer
2k views

What are the drawbacks of using Galera Cluster instead of Master/Slave Replication?

What are the drawbacks of using Galera Cluster instead of regular Master/Slave Replication? Galera's 0 slave lag time, Synchronous replication and no Single point of failure seem very appealing then ...
5
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2answers
3k views

Does a TRIGGER improve the performance?

I understand that TRIGGERs are useful, as they take care of subsequent queries, but do they have an advantage from performance point of view too? Replacing two or three queries as INSERT INTO table1 ...
0
votes
2answers
922 views

Warning before issuing delete/update command in mysql/oracle , then executes

Is there any utility , function either in mysql /oracle that if i issue some delete/update command wrongly , a message must prompt at command_line* (if possible in ubuntu) asking whether "you sure to ...
3
votes
1answer
1k views

Rare error lasts only a second “Can't connect to local MySQL server through socket '/tmp/mysql.sock' (146)” 146=ECONNREFUSED

This is a rare error that occurs on Solaris 10, have seen it from Perl, where this line DBI->connect(...) or die "Whoops! $DBI::errstr" outputs Whoops! Can't connect to local MySQL server through ...
1
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0answers
221 views

Cumulative Function in MySQL

i have a problem creating cumulative function in mysql database. let say i have a stored procedure which getting data and counting quantity/sum_quantity example A table consist of consumer goods ...