Russell Francis wrote:
> If a SELECT statement contains a table in it's FROM clause which has 0
> records in it, the query will not return any results. If a record is added
> to the table even though it shouldn't modify the results of query, the query
> will return the expected result.
>
> The SQL statements below are a trimmed down test case which duplicates this
> issue. The identical SELECT statements return different results depending
> on the record count of the unrelated table_b.
>
> SELECT table_a.* FROM table_a, table_b WHERE table_a.ta_col_a > 0;
table_b is certainly not unrelated, as it appears in the FROM clause.
So the query is correct to not show any result, per definition of
cartesian product.
--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support
