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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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MySQL “NOT IN” query
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NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL in MySQL
MySQL, as well as all other systems except SQL Server, is able to optimize LEFT JOIN / IS NULL to return FALSE as soon the matching value is found, and it is the only system that cared to document this behavior.
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Mysql: Select rows from a table that are not in another
... this only works as expected when none of the columns have NULL values. In MySQL NULL != NULL so every row that has a NULL value will be returned even if there is a duplicate row in the second table.
– Kyle Kochis
Apr 7 '15 at 2:49
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PostgreSQL Autoincrement
I'm switching from MySQL to PostgreSQL and was wondering how I can do autoincrement values. I saw in the PostgreSQL docs a datatype "serial", but I get syntax errors when using it (in v8.0).
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MySQL “WITH” clause
I'm trying to use MySQL to create a view with the "WITH" clause
8 Answers
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Using backticks around field names
...ering if there's anything wrong with using backticks around field names in MySQL.
11 Answers
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Increment value in mysql update query
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You could also just do this:
mysql_query("
UPDATE member_profile
SET points = points + 1
WHERE user_id = '".$userid."'
");
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
... Having a problem with a similar situation in PhpMyAdmin over MySQL. In my case, the source and destination columns are in the same table, but record selection is based on the other table. The "SELECT" version of the query works, but the UPDTATE statement throws a syntax error at "FRO...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
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How do we solve it?
Use long data types (64 bits is sufficient)
For MySQL (or MariaDB), if you don't need the time information consider using the DATE column type. If you need higher accuracy, use DATETIME rather than TIMESTAMP. Beware that DATETIME columns do not store information about the ...
MySQL offset infinite rows
...ble, but is offset by 5 from the start of the table. As far as I can tell, MySQL's LIMIT requires a limit as well as an offset. Is there any way to do this?
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