Re: BUG #2503: Query results differ based on record count of unrelated table.

[Alvaro Herrera <alvherre(at)commandprompt(dot)com>]

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/
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