Aamir Mahmood
Reputation: 2724
Mysql where condition on columns
Minimal example
select a.order_id as X from orders as a
WHERE
X > 8000
query will fail as X is not a column, any solution?
other example
select (if (E.size > 0, E.Size, (B.height x B.width)) as sizeX from
orders as a, report as E, size as B
where
(E.id = a.id and B.id = a.id)
and
sizeX > 100
my query may contain typos, but I hope my question is clear
Upvotes: 1
Views: 58
Answers (2)
Stephan
Reputation: 8090
You have 2 options:
1) Use HAVING (not very efficient since the conditions from having clause are applied AFTER the results are returned and thus NO indexes are used)
select a.order_id as X from orders as a
HAVING
X > 8000
2) Use the column name (efficient if you have a index an the column used in where clause)
select a.order_id as X from orders as a
WHERE
a.order_id > 8000
Upvotes: 3
