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How can I append a string to an existing field in MySQL?
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You need to use the CONCAT() function in MySQL for string concatenation:
UPDATE categories SET code = CONCAT(code, '_standard') WHERE id = 1;
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Bogus foreign key constraint fail
...Two possibilities:
There is a table within another schema ("database" in mysql terminology) which has a FK reference
The innodb internal data dictionary is out of sync with the mysql one.
You can see which table it was (one of them, anyway) by doing a "SHOW ENGINE INNODB STATUS" after the drop f...
MySQL - Using COUNT(*) in the WHERE clause
I am trying to accomplish the following in MySQL (see pseudo code)
9 Answers
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Find rows that have the same value on a column in MySQL
... created what was essentially infinite recursion or something on mysql resulting in a dead database due to "too many connections" :-/
– huygir
Mar 5 '18 at 17:40
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Delete all records in a table of MYSQL in phpMyAdmin
... detailed blog with example: http://sforsuresh.in/phpmyadmin-deleting-rows-mysql-table/
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Add 2 hours to current time in MySQL?
Which is the valid syntax of this query in MySQL?
5 Answers
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Update one MySQL table with values from another
I'm trying to update one MySQL table based on information from another.
2 Answers
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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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MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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Is there documentation for the Rails column types?
...ded by Rails mostly for compatibility with database systems. For instance, MySQL's TIMESTAMP datatype is stored as a unix timestamp. Its valid range goes from 1970 to 2038, and the time is stored as the number of seconds that have elapsed since the last epoch, which is supposedly standard, but in pr...