[RESOLVED] getting NULLS instead of NOT NULLS ORS and ANDS

[jrough]

I don't understand what is going on. I run this query and I get all records that are null? So is it checking the first OR clause and then stopping.

SELECT item_descr from mydb.mytable WHERE
substr(filename,5,3) = 052 OR substr(filename,5,3) = 060 AND item_descr IS NOT NULL

What I want is to find all the rows where there is something in the item_descr field
in the rows that are for filename 052 or 060.

To make it more complicated there are also filenames that are different.
OR substr(filename,1,6)='SUBJOB' AND (substr(filename,8,3)='060' ) ) OR

(substr(filename,1,3)='NOF' AND (substr(filename,5,3)='060' ) )

I would like to check if there is an item_descr in those rows also but I could run the above one at a time for the subjob and nof.
thanks,

[bradgrafelman]

AND has a higher precedence than OR, so "x OR y AND z" is the same as "(x) OR (y AND z)".

If that's not what you want (which apparently it isn't), then use parenthesis to group the expressions according to the logic you want.

[Crowly]

The IN operator can simplify the where statement a little bit, and substr returns a string, so you need to include the values in '

SELECT item_descr from `mydb`.mytable WHERE
substr(filename,5,3) IN ('052','060') AND item_descr IS NOT NULL

[jrough]

thanks for noticing the missing 's
the IN does make it easier to read.
I couldn't really tell if the query was correct because it didn't return data but I will run it again.

[bradgrafelman]

The quotes aren't really required, but it does make more sense to use them.