Re: Views With Unions

On Thu, 31 Jul 2003, Christopher Browne wrote:

> select * from log_table where request_time between 'june 11 2003' and
> 'june 12 2003';
>
> returns a plan:
> Subquery Scan log_table (cost=0.00..10950.26 rows=177126 width=314)
> -> Append (cost=0.00..10950.26 rows=177126 width=314)
> -> Subquery Scan *SELECT* 1 (cost=0.00..3089.07 rows=50307 width=71)
> -> Seq Scan on log_table_1 (cost=0.00..3089.07 rows=50307 width=71)
> -> Subquery Scan *SELECT* 2 (cost=0.00..602.92 rows=9892 width=314)
> -> Seq Scan on log_table_2 (cost=0.00..602.92 rows=9892 width=314)
> -> Subquery Scan *SELECT* 3 (cost=0.00..2390.09 rows=39209 width=314)
> -> Seq Scan on log_table_3 (cost=0.00..2390.09 rows=39209 width=314)

What version are you using? In 7.3 and up it should be willing to
consider moving the clause down, unless there's something like a type
mismatch (because in that case it may not be equivalent without a bunch
more work on the clause).