That is bizarre. Does EXPLAIN show any difference?
---------------------------------------------------------------------------
Merlin Moncure wrote:
> I have a strange but reproducible problem where a query does not seem to
> return the same results.
>
> esp=# select 1::int4, * from data1.po_line_file
> esp-# where pol_po_no = '00000002' and
> esp-# (pol_po_no = '00000002' and pol_po_rel_no = 0) and
> esp-# (pol_po_no = '00000002' and pol_po_rel_no = 0 and
> pol_item_no = '1570')
> esp-# limit 1 ;
> [fields omitted]
> (0 rows)
>
> esp=# select 1::int4, * from data1.po_line_file
> esp-# where --pol_po_no = '00000002' and
> esp-# --(pol_po_no = '00000002' and pol_po_rel_no = 0) and
> esp-# (pol_po_no = '00000002' and pol_po_rel_no = 0 and
> pol_item_no = '1570')
> esp-# limit 1 ;
> [fields omitted, note commented redundant clauses]
> (1 row)
>
> The obviously silly Boolean clause here was sql that was generated by a
> driver. I recoded the driver to make more intelligent sql and now the
> problem is gone, at least from my application. Note that the same query
> form but with different tables/fields works correctly 99.99999% of the
> time, just not this time...I'm just curious as to how two seemingly
> equivalent statements could produce different results...perhpaps I
> missed something?
>
> Merlin
>
>
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-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
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