At 15:30 -0600 1/18/02, Rick Emery wrote:
Is this a bug? I can't find an answer to this question in FAQs or archives.
CREATE TABLE aa ( a int);
INSERT INTO aa VALUES (1),(2),(3),(2),(4),(5),(1),(6),(3);
the following :
mysql> select a,count(*) as z from aa where z>1 group by a;
displays this error:
ERROR 1054: Unknown column 'z' in 'where clause'
Why isn't z recognized as a column identifier?
As others have pointed out, your query requires a HAVING rather than a
WHERE. What hasn't been pointed out, which is worth knowing, is that
column aliases cannot be used in *any* WHERE clause.