Reputation: 49
With a HTML/php Webinterface i am putting some variables to a mysql datebase. The query works fine like this:
INSERT INTO ". $tabledb_stack ." (ANr, Operator) VALUES ('". $ANr ."', '". $Operator ."')
But now i need to check if the ANr Value is already in the database. But just the ANr number and no other Value. Then it should not write it into the database. I tried with a WHERE NOT EXISTS statement, but it isnt working.
Any hints how i can try it?
Thx
Upvotes: 0
Views: 95
Reputation: 177
If the ANr
column has a primary or unique key assigned to it, then it is possible to use INSERT INTO x ON DUPLICATE KEY UPDATE ANr = ANr
so it will not update any rows, if the ANr
will have any existing rows not depending on Operator
column.
In case ANr
can have more than one Operator
it is possible to use INSERT IGNORE INTO
. Thus it will ignore the insert, if there will be an existing row with ANr + Operator
already.
For more information, feel free to read MySQL documentation here - https://dev.mysql.com/doc/refman/8.0/en/insert.html
Upvotes: 1