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MySQL search and replace some text in a field
What MySQL query will do a text search and replace in one particular field in a table?
7 Answers
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Add Foreign Key to existing table
...is link. It has helped me with errno 150:
http://verysimple.com/2006/10/22/mysql-error-number-1005-cant-create-table-mydbsql-328_45frm-errno-150/
On the top of my head two things come to mind.
Is your foreign key index a unique name in the whole database (#3 in the list)?
Are you trying to set th...
MySQL Error 1215: Cannot add foreign key constraint
...the 4th point was my problem. It's kind of nasty - but I'm very very happy mysql did crash for that
– Sebas
Jun 16 '16 at 15:21
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Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTIT...
Database development mistakes made by application developers [closed]
... exists--you should be using it.
It's quite common to see this failure on MySQL databases. I don't believe MyISAM supports it. InnoDB does. You'll find people who are using MyISAM or those that are using InnoDB but aren't using it anyway.
More here:
How important are constraints like NOT NULL...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...cally, a lot of dbms have been quite poor when it comes to handling joins (MySQL being a particularly noteworthy example). So n+1 has, often, been notably faster than a join. And then there are ways to improve on n+1 but still without needing a join, which is what the original problem relates to.
H...
Export to CSV via PHP
...p, $fields);
}
fclose($fp);
?>
First you must load the data from the mysql server in to a array
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mysql check collation of a table
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Works for me in mysql 5.5.52. ...) ENGINE=InnoDB AUTO_INCREMENT=24 DEFAULT CHARSET=latin1 My guess is it may not show the collation if it is set to the default for the database in later versions of mysql/mariadb.
– Deve...
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