Question

I have a single table as follows:

+---+----------+----------+---------+---------+
+ID + FIELD 1  + FIELD 2  + FIELD 3 + FIELD 4 +
+---+----------+----------+---------+---------+
+ 1 +  AAA     +  1234    +  ABC    +   Y     +
+ 2 +  AAA     +  1234    +  DEF    +         +
+ 3 +  AAA     +  1234    +  GHI    +         +
+ 4 +  BBB     +  1234    +  ABC    +         +
+ 5 +  CCC     +  1234    +  JKL    +         +
+---+----------+----------+---------+---------+

I have a process running that may set FIELD4 to “Y” and then a second process that checks for the value of ‘Y’ in a FIELD4.

I need to write a query (or queries probably) that will delete the record where FIELD4 = ‘Y’, but then also delete all other records where FIELD1 is of the same value to that of the originally deleted record.

For the record, FIELD4 will eventually become a check box and the MySQL required will be called from within a PHP script. With this in mind, if the solution involves PHP this would not be an issue.

I’ve had a good search around PHP and MySQL sites and forums, but can’t locate a One to Many deletion. Any ideas out there?

Answer 1

Try with following query:

delete from table
where FIELD1 in (
    select a.FIELD1
    from (select * from table) a 
    where a.FIELD4='Y'
);