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Generic MySQL version 5 tag. Please use a mysql-5.x tag instead. Also tag with mysql for search purposes.

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Signal handler on mysql connection break

I want to know if there is any signal that I can catch by which I can know that my mysql connection with the server has broken in c programming? I know I can check at query time whether my connection ...
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1answer
3k views

MySQL Master 5.5 - Slave 5.6 - unknown system variable 'binlog_checksum', Error_code: 1193

I see the below warning on the my slave server: 2016-11-18 22:48:03 12808 [Warning] Slave SQL: If a crash happens this configuration does not guarantee that the relay log info will be consistent, ...
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1answer
382 views

Will a mysql db import be interrupted if my ssh session times out?

I have a large-ish (several GB) mysql DB that I'm planning to import via mysql -u root -p mydb < mydb.sql in a SSH session. What would happen if my SSH connection drops? Is it safer to run ...
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4k views

Create Table. Foreign key constraint is incorrectly formed

I have my sql query SET FOREIGN_KEY_CHECKS=0; CREATE TABLE IF NOT EXISTS `cms_pages` ( `id` int(11) NOT NULL, `chain_id` int(11) NOT NULL, `default_title` varchar(255) DEFAULT NULL, `created` ...
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3answers
3k views

MySQL secure random string generator

I am looking to generate a cryptographically secure string for password reset in MySQL. I know I could do this at the application level in PHP; but that requires the OpenSSL extension which many of my ...
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2answers
7k views

Computed/Generated columns in MySQL 5

How do I create a table with a formula column in MySQL version 5? For example: I have a table named Product, which has 5 columns: id int, amount int, sold_out int, faulty int, remain_amount is (...
3
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1answer
1k views

MySQL v5.1.73 - can the binlog_format betweem Master & slave be different?

We are in the process of testing MySQL replication before using it in production. The MySQL is being setup by Puppet in our case and I noticed that the binlog_format setting is different between ...
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1answer
2k views

Exclude entries from SELECT COUNT

I'm new to MySQL and I have a problem with one task. I have a table like this: +------------+------------+-------------+ | code | name | location | +------------+------------+----------...
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3answers
5k views

Table Design for Student Attendance hourly for each day

I have created a table (attendance_details) for storing every day attendance of Students in MySQL. Need to capture attendance for hourly (1-8hrs) every day. I have the student details in separate ...
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1answer
350 views

MySQL UTF-8 Encoding Problem

I have two MySQL databases that are for Wordpress websites. One db is for a live version of a site, the second is a copy of the original that is used in conjunction with a copy of the original site. ...
0
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1answer
99 views

Trying to avoid bad MySQL database design - can't figure out how to avoid too many columns

I am pretty much a beginner having only created a few small php web applications relying on a MySQL database. I am now working on a somewhat larger project. I am in the planning stages of setting up ...
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2answers
364 views

SELECT WHERE CASE

I have the following table (MySQL): -------------------------------------------------------- | id |product_id| store_id | stock_id | priority | --------------------------------------------------...
4
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1answer
223 views

Find clients who bought more than 1 million units in 3 consecutive months

I want to find the client's code (cCode), who bought more than 1 million units, in three consecutive months. Here is my data: gDate cCode buy 2014-10-22 15108164 1653410 2014-12-22 ...
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1answer
66 views

How to properly aggregate?

I have a table for logs with over 6 million records. I want a query that shows me all the occurrences where the src goes to the same destination/port. I tried this: SELECT src, dst, dstport, COUNT(...
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0answers
2k views

Combine and display multiple row data with same column data in MySQL

I have a menu, from where every item ordered is stored in a row. For a single order, there can be multiple rows.What I want is that when I display it, for same order_number ( number) all rows data is ...
2
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1answer
1k views

Is there a way to run mysqldumpslow against slow queries logged to a table?

AWS RDS by default logs slow queries to a database table. Is there a way to run mysqldumpslow against that table, without exporting it to a file first? Or is there a better way to get a report of ...
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3answers
1k views

Question on having a MySQL 5.1 replicate from a MySQL 5.6 DB

I have a question in regards of what potential issues that might happen with a MySQL 5.1 DB that replicates from a MySQL 5.6 DB. I know the risks involved based on resources such as http://dev....
0
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1answer
48 views

Mysql query performance

We have a database table and we found a weird query from old code. We can't really explain it, so we decided to analyze why it could have been done that way. The weird thing is that the results are ...
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0answers
43 views

MySQL stops unexpectedly on CentOS 6.5 with WHM/Cpanel after migrating server with transfer tool [duplicate]

I recently moved my entire websites from a dedicated CentOS5 server to a CentOS 6.5 on Amazon EC2 with the same cPanel/WHM version. WHM 11.44.1 (build 19) However after angry calls from clients I ...
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4answers
108 views

Why does this query take 32 sec to execute?

I keep my history records in one table and my pertinent data in another. I want to grab only the files from myfiles that currently have a given status recorded in statuses (ie, the latest status is ...
6
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1answer
11k views

Any known issues upgrading from MySQL 5.1.73 to 5.6.21?

I am planning my MySQL DB ver5.1.73 running on a CentOS 6.5 machine to MySQL 5.6.21. I understand the basic procedure for this based on what I have read on StackOverflow, but I was curious if anyone ...
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2answers
435 views

Fourth inner join to the same table increases query duration significantly

As soon as I add a fourth inner join to a specific table, the query duration increases significantly: sub 1sec to 45sec. The table in question is deployments d4. The SQL Query: select a.id as ...
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2answers
4k views

How to check/change MySQL named pipe settings?

I'm having a hard time finding anything on this because I don't know what to call it. But when you install MySQL it asks you if you want to allow connections to the database from other machines or ...
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3answers
1k views

How to rewrite subquery to return only 1 row

I need to somehow check if query result is NULL, MySQL returns error Subquery returns more than 1 row. How should I rewrite it in order to work correctly please? SELECT DISTINCT user.id, user....
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1answer
465 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
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1answer
88 views

How to do Mysql migration from 5.0 (320bit windows) to 5.6 (64 bit windows)?

I want migrate My Mysql 5.0 windows 32 bit to Mysql 5.6 Windows 64 bit? Please suggest me the best way to do migration, i have around 10gb of data present in Mysql 5.0.
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2answers
19k 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 34459393 ...
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1answer
38 views

Omitting [INTO] in the INSERT … SELECT statement

Does the INTO keyword only makes the query more readable, or does it bring another benefits as well? The queries beneath both seem to run equivalently . insert ignore tbl (type, details) values ('1', ...
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0answers
521 views

Unable to install mysql 5.6.17and configure mysql on Win 7 -64 bit Os

Already seen this post but not my type of question as iam stuck in the installation itself I am trying to install MySQL 5.6.17 on Windows 7 64-bit Operating System. Everytime I try I am stuck in this ...
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2answers
777 views

Remove all duplicate data in mysql

I want remove all duplicate data from my table. anyone help me. my table : biblio one one two three three four five i want to get result like this biblio two four five
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2answers
3k views

MySQL Community Edition Capacity

I am using MySQL Community Edition on Amazon RDS service. It is a very large database, 2/3 tables has about 10 millions records and 4-5 tables has 7-8 millions records. Questions How much capacity ...
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1answer
631 views

How to include a semicolon (“;”) in a MySQL pager command

I've just discovered the pager command in the MySQL command-line client, and I'm having a tonne of fun. This blog post is great: http://www.mysqlperformanceblog.com/2008/11/21/how-to-calculate-a-good-...
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3answers
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Why query_cache_type is disabled by default start from MySQL 5.6?

We've upgraded to MySQL 5.6 and start seeing the loading of db server increased significantly, and finally found out the query_cache_type is defaulted to off start from 5.6. We enabled it again and ...
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2answers
456 views

Keywords - column or separate table

I am building a website on MySQL with php, and I have 400+ products in a table. I have three columns with comma separated values, each has 1-3 values separated by commas in each row. I was wondering ...
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2answers
2k views

How to select the latest record of each hour in a day?

I want to select the latest record of each hour in a given date, based on the datetime column 'reading_on' in my table. What is the best way to do it? I already tried group by HOUR(reading_on) with ...
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3answers
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MySQL: How to avoid case sensitivity in SQL queries when migrate from Windows to Linux?

I have migrated my Database from Windows to Linux server. In many places, query has been written without focusing their cases (uppercase / lowercase). So, these queries are not getting executed and ...
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2answers
5k views

Why is MySQL not using the index with the higher cardinality?

I have an index called source with cardinality of 1122 and a second index called state with cardinality of 22. MySQL keeps using the state index when when query SELECT C1 FROM tbl WHERE source = 'x' ...
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3answers
334k views

ALTER TABLE - Rename a column

This is driving me nuts! I want to rename a column from read-more to read_more in my blog table I tried all this: ALTER TABLE blog RENAME COLUMN read-more to read_more; ALTER TABLE blog CHANGE ...
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3answers
586 views

How to update cust_id from Customer table to order table Cust_id field while inserting customer name using trigger

I have two tables 1. Customer_details and 2. Order_details. 1.Customer_details table -->fields--> Cust_Id(Primary Key) and Customer_Name, 2.Order_details table --> fields-- Ord_Id(Primary Key),...
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1answer
15k views

MySQL rebuild after Corrupt ibdata1

I have a MySQL server that serves a couple of databases including a Magento e-commerce store. We have been suffering with corruption in the ibdata1 file for a while, but it has now reached a critical ...
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2answers
1k views

Why does MySQL fail to use an index effectively when LIMIT offset is large?

I do not understand when querying 5 rows from a table of 500,000 rows, the following query takes 0.00sec: SELECT id, username FROM Users FORCE INDEX (PRIMARY) ORDER BY id LIMIT 20,5; But querying ...
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2answers
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Find problematic MySQL users and databases

We have a MySQL 5.1 server that is an "open" service: anyone on campus can request a database. As such, we have several thousand databases on this one server. As you might imagine, sometimes one user'...
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1answer
88 views

Mysql query in Database

How to get all the tables from database with all values in tables using single query.. I tried using $sql = "SHOW TABLES FROM $dbname"; $result = mysql_query($sql); $arrayCount = 0 while ($row = ...
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4answers
28k views

Can't remote access MySQL server running on Mac OS X

I have a MySQL server running on my work computer, which runs Mac OS X Maverick. I want to access it from home computer, which also has Mac OS Maverick. From terminal, if in 1 tab, I ssh into my ...
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2answers
2k views

Getting table definitions on the command line in MySQL [closed]

I am new to MySQL. I am trying to get table definitions from the database server (4.0.26). I tried below steps to get information, running cmd as an administrator: c:\> cd mysql\bin\ c:\mysql\bin&...
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2answers
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InnoDB: Error: Table “mysql”.“innodb_table_stats” not found after upgrade to mysql 5.6

I upgraded to mysql 5.6 from 5.5, and now my logs are littered with such messages on startup I found a possible solution here, but it does not seem official. http://forums.mysql.com/read.php?22,...
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1answer
2k views

mysql 5.1 — unknown variable 'basedir=c:/mysql/'

I recently changed the default port(3306) to another for mysql. I did it by changing the my.ini file and did restart of the server. No other changes were made whatsoever. When connecting using a GUI ...
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2answers
12k views

How to force higher values of open_files_limit or table_open_cache?

I'm having a frustrating problem where setting my.cnf to values higher than I currently have them does not 'take'. This is MySQL 5.6.14 on MacOS X 10.8.3 I'm trying to address dropped connections ...
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1answer
17k views

Selecting multiple columns from multiple rows in one column (subquery?)

I'm working with MySQL 5.1.68. I have a situation where I'd like to select rows from another table into a column. I'd like to output this: id # name # citizen_name (multiple citizen names) 1 # The ...
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1answer
1k 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 and ...