On 05 Nov 2012 23:10, Birgitta Hauser wrote:
It [<ed:> the query] simply uses the access path of the logical
file, but not the logical file itself, i.e. it ignores the
That a query could use the AccPth while ignoring the Slt\Omt
specifications can be true *only* for a DYNSLT LF. Without a Dynamic
Select specification in the DDS, a Keyed Access Path actually includes
or omits the rows with the Access Path itself, so there would be no
ability for the query to ignore those specifications when implementing
with that AccPth. Whether that has any relevance for the OP scenario is
unknown by me; unstated by the OP.
As an aside an SQL index has (per default) a page size of 64 K (while
the default page size for a DDS described logical file is 8K), i.e.
performance may be better.
The PagSiz for a keyed DDS PF or LF is calculated based on the size
of the key; i.e. there is no one specific default. A parameter kwd was
added to the CRTLF and CRTPF to enable specification of the Page Size;
the default is *CALC. IIRC a "short" key actually uses a 4K page size,
and smaller page sizes can be better for non-query [RLA] activity and
effects on journal; i.e. for effective memory footprint.