[sql] How to write a SQL DELETE statement with a SELECT statement in the WHERE clause?

Database: Sybase Advantage 11

On my quest to normalize data, I am trying to delete the results I get from this SELECT statement:

SELECT tableA.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
;

This is the DELETE statement I have come up with:

DELETE FROM tableA
WHERE (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'))
;

I continuously get this error when I try to run this statement:

ERROR IN SCRIPT: poQuery: Error 7200:  AQE Error:  State = S0000;   NativeError = 2124;
[iAnywhere Solutions][Advantage SQL Engine]Invalid operand for operator: = Boolean value
cannot be operated with non-Boolean value.

I have also tried this statement:

DELETE FROM tableA 
INNER JOIN tableB u on (u.qlabel = tableA.entityrole AND u.fieldnum = tableA.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR tableA.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')
;

Which results in:

ERROR IN SCRIPT: poQuery: Error 7200:  AQE Error:  State = 42000;   NativeError = 2117;
[iAnywhere Solutions][Advantage SQL Engine] Unexpected token: INNER -- Expecting semicolon.
-- Location of error in the SQL statement is: 23 (line: 2 column: 1)

Could someone aid me in properly constructing a DELETE query that will result in the proper data being removed?

Your second DELETE query was nearly correct. Just be sure to put the table name (or an alias) between DELETE and FROM to specify which table you are deleting from. This is simpler than using a nested SELECT statement like in the other answers.

Corrected Query (option 1: using full table name):

DELETE tableA
FROM tableA
INNER JOIN tableB u on (u.qlabel = tableA.entityrole AND u.fieldnum = tableA.fieldnum) 
WHERE (LENGTH(tableA.memotext) NOT IN (8,9,10)
OR tableA.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')

Corrected Query (option 2: using an alias):

DELETE q
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date')

More examples here:
How to Delete using INNER JOIN with SQL Server?

Shouldn't you have:

DELETE FROM tableA WHERE entitynum IN (...your select...)

Now you just have a WHERE with no comparison:

DELETE FROM tableA WHERE (...your select...)

So your final query would look like this;

DELETE FROM tableA WHERE entitynum IN (
    SELECT tableA.entitynum FROM tableA q
      INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
    WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
      AND (u.FldFormat = 'Date')
)

Did something like that once:

CREATE TABLE exclusions(excl VARCHAR(250));
INSERT INTO exclusions(excl)
VALUES
       ('%timeline%'),
       ('%Placeholders%'),
       ('%Stages%'),
       ('%master_stage_1205x465%'),
       ('%Accessories%'),
       ('%chosen-sprite.png'),
('%WebResource.axd');
GO
CREATE VIEW ToBeDeleted AS 
SELECT * FROM chunks
       WHERE chunks.file_id IN
       (
       SELECT DISTINCT
             lf.file_id
       FROM LargeFiles lf
       WHERE lf.file_id NOT IN
             (
             SELECT DISTINCT
                    lf.file_id
             FROM LargeFiles lf
                LEFT JOIN exclusions e ON(lf.URL LIKE e.excl)
                WHERE e.excl IS NULL
             )
       );
GO
CHECKPOINT
GO
SET NOCOUNT ON;
DECLARE @r INT;
SET @r = 1;
WHILE @r>0

BEGIN
    DELETE TOP (10000) FROM ToBeDeleted;
    SET @r = @@ROWCOUNT  
END
GO

in this scenario:

DELETE FROM tableA
WHERE (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'));

aren't you missing the column you want to compare to? example:

DELETE FROM tableA
WHERE entitynum in (SELECT q.entitynum
FROM tableA q
INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
WHERE (LENGTH(q.memotext) NOT IN (8,9,10) 
OR q.memotext NOT LIKE '%/%/%')
AND (u.FldFormat = 'Date'));    

I assume it's that column since in your select statement you're selecting from the same table you're wanting to delete from with that column.