Question

I have a question regarding an SQL syntax.

I have a mysql table like this (id, name, subid, preview) where preview is set to 0 as default. So now I want to make a select to query only lines where preview is different from zero.

Can I do this in a single query .. or I need to query all and then make (if else) decisions?

like SELECT * FROM table_name; – and iterate through … ?

Answer 1

You could do

select *
from mytable
where preview != 0 

!= means “not equal to”. Some databases also use <> for the same meaning.

If preview is nullable, do you also want to return rows where preview is null? If so, you may want to try:

select *
from mytable
where preview != 0 or preview is null