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MySQL: how to get the difference between two timestamps in seconds
Is there a way I can make a query in MySQL that will give me the difference between two timestamps in seconds, or would I need to do that in PHP? And if so, how would I go about doing that?
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SQL/mysql - Select distinct/UNIQUE but return all columns?
...ause the behavior on the other columns is unspecified. (The first works in MySQL, if that's what you're using.)
You could fetch the distinct fields and stick to picking a single arbitrary row each time.
On some platforms (e.g. PostgreSQL, Oracle, T-SQL) this can be done directly using window funct...
MySQL WHERE: how to write “!=” or “not equals”?
...ered Jul 10 '12 at 20:53
RolandoMySQLDBARolandoMySQLDBA
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MySQL - why not index every field?
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The link is for MS SQL Server; this question is for MySQL
– OMG Ponies
Mar 26 '11 at 23:38
6
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MySQL: Order by field size/length
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@mastazi according to MySQL documentation: OCTET_LENGTH() is a synonym for LENGTH().
– Heitor
Oct 1 '17 at 5:35
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Is there a MySQL option/feature to track history of changes to records?
I've been asked if I can keep track of the changes to the records in a MySQL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
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Multiple queries executed in java in single statement
...BC as it currently provides an exception even though it is possible in the MySQL query browser.
6 Answers
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How do I rename a column in a database table using SQL?
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This is not supported in MySQL, is it?
– ustun
Oct 21 '11 at 11:41
5
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MySQL - ORDER BY values within IN()
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@Vladimir - yes, it is MySQL-specific. The question has the mysql tag.
– Ayman Hourieh
Jun 6 '09 at 1:10
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How do I find which transaction is causing a “Waiting for table metadata lock” state?
...ransactions waiting for locks:
SELECT TRX_ID, TRX_REQUESTED_LOCK_ID, TRX_MYSQL_THREAD_ID, TRX_QUERY
FROM INNODB_TRX
WHERE TRX_STATE = 'LOCK WAIT';
Reference - MySQL Troubleshooting: What To Do When Queries Don't Work, Chapter 6 - Page 96.
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