Comparing a function result and subselect in MYSQL where clause

Asked Mar 07 '18 at 14:44

Active Mar 07 '18 at 14:44

Viewed 185 times

I can't figure out why this subselect doesn't return anything.

select value from mytable where 
indx = @var
and f() in (select num from nums);

when this version does:

select value from mytable where 
indx = @var
and f() in (2,5,11);

When I create a list identical to the results from the subselect, it works, but when using a subselect doesn't.

Also, this works:

select value from mytable where 
indx = @var
and 2 in (select num from nums);

asked Mar 07 '18 at 14:44

ShawnInAA

Show what the `nums` table looks like. – Gordon Linoff Mar 07 '18 at 14:49
`insert into nums values (2),(5),(11);` Just a simple table for this example. – ShawnInAA Mar 08 '18 at 21:56
What does "doesn't return anything" mean? Does it return no rows? Does it return rows with `NULL`values? Does it just hang? Does it return an error? – Gordon Linoff Mar 09 '18 at 13:11
The first query returns no rows. The second and third query return one row. – ShawnInAA Mar 12 '18 at 13:33

0 Answers0