[postgis-users] Mapserver layer selects

[Paul Ramsey]

The first query refers to a table 'swip2' and the succeeding ones
refer to 'swip3'. Also, the point returned in the third query is
*different* that the one returned in the first.

P

On Wed, Feb 11, 2009 at 8:27 PM, Stephen Davies <sdc at sdc.com.au> wrote:
> Could somebody please help me explain the results below.
>
> The selects are cut-and-paste from postgresql log of cursor creation commands
> from mapserver.
> Both refer to the same point entity and both have the same map extent
> constraint but the first query (correctly) returns one row while the second
> returns none.
>
> However, removing the extent constraint from the second query to give the
> third, succeeds in returning the correct row.
>
> Given that this is the only difference between queries 2 and three, one would
> have to assume that the point is outside the extent.
>
> However, query 1 shows that the point is actually in the extent - as does
> eyeballing the geometries.
>
> To further confuse me, increasing the extent in query 2 eventually results in
> the entity being returned.
>
> Cheers and thanks,
> Stephen Davies
>
> benparts=# SELECT * from swip2 WHERE (pid in (select probe.id from probe where
> logger_id in (select id from logger where client_id=120)) and
> rdate='2009-02-12 13:30:00') and (geom &&
> setSRID( 'BOX3D(138.5356633 -34.9225467,138.5397151 -34.9184949)'::BOX3D,4283) );
>        rdate        | state  | pid | location |                        geom
> ---------------------+--------+-----+----------+----------------------------------------------------
>  2009-02-12 13:30:00 | 13.000 | 607 | Oval     |
> 0101000020BB1000007ADFF8DA335161406551D845D17541C0
> (1 row)
>
> benparts=# SELECT * from swip3 WHERE (pid in (select probe.id from probe where
> logger_id in (select id from logger where client_id=120)) and
> rdate='2009-02-12 13:30:00') and (geom &&
> setSRID( 'BOX3D(138.5356633 -34.9225467,138.5397151 -34.9184949)'::BOX3D,4283) );
>  id | zname | pid | geom | rdate
> ----+-------+-----+------+-------
> (0 rows)
>
> benparts=# SELECT * from swip3 WHERE (pid in (select probe.id from probe where
> logger_id in (select id from logger where client_id=120)) and
> rdate='2009-02-12 13:30:00');
>  id | zname  | pid |                        geom                        |
> rdate
> ----+--------+-----+----------------------------------------------------+---------------------
>  28 | Zone 2 | 607 | 0101000020BB1000007ADFF8DA335161406551D845D17541C0 |
> 2009-02-12 13:30:00
> (1 row)
>
> --
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