%_Hints Statement Explanation (RSWWCOND)

[Former Member]

Hi Everyone,

I would appreciate any help you could give me on this. Basically I'm analyzing the standard program RSWWCOND to evaluate it's performance, how it works, etc. There is a Select statement contained within the program and the notation has just confused me a bit. The Select statement uses hints in the where clause (%_HINTS) which is fine. ::

SELECT wi_id INTO CORRESPONDING FIELDS OF TABLE lt_swwwihead

FROM swwwihead

WHERE

wi_type IN type AND

wi_stat EQ swfco_wi_status_checked AND

wi_rh_task IN task "Note 748688

%_HINTS DB2 'USE VALUES FOR OPTIMIZATION'

DB2 '&SUBSTITUTE VALUES&'

ORACLE 'INDEX("&TABLE&" "SWWWIHEAD~C" "SWWWIHEAD^C")'.

However one part of the statement is confusing me and that is the last line ::

ORACLE 'INDEX("&TABLE&" "SWWWIHEAD~C" "SWWWIHEAD^C")'.

I'd appreciate is someone could explain to me what the hat (^{) symbol is doing when used in "SWWWIHEAD}C" . I've search around and can't seem to find anything to explain this notation.

Sincere thanks for your time.

Regards,

Damien

[Former Member]

Hi Everyone,

I would appreciate any help you could give me on this. Basically I'm analyzing the standard program RSWWCOND to evaluate it's performance, how it works, etc. There is a Select statement contained within the program and the notation has just confused me a bit. The Select statement uses hints in the where clause (%_HINTS) which is fine. ::

SELECT wi_id INTO CORRESPONDING FIELDS OF TABLE lt_swwwihead

FROM swwwihead

WHERE

wi_type IN type AND

wi_stat EQ swfco_wi_status_checked AND

wi_rh_task IN task "Note 748688

%_HINTS DB2 'USE VALUES FOR OPTIMIZATION'

DB2 '&SUBSTITUTE VALUES&'

ORACLE 'INDEX("&TABLE&" "SWWWIHEAD~C" "SWWWIHEAD^C")'.

However one part of the statement is confusing me and that is the last line ::

ORACLE 'INDEX("&TABLE&" "SWWWIHEAD~C" "SWWWIHEAD^C")'.

I'd appreciate is someone could explain to me what the hat (^{) symbol is doing when used in "SWWWIHEAD}C" . I've search around and can't seem to find anything to explain this notation.

Sincere thanks for your time.

Regards,

Damien

[Former Member]

you statement has two hints for IBM DB2 databases and for oracle databases,

the oracle hints tell the optimizer to use a certain index, which is the index C.

these are two internal names for the same index: SWWWIHEAD~C" "SWWWIHEAD^C"

the optimizer picks the one it knows.

Siegfried

[Former Member]

Siegfried,

Thank you very much for taking the time to provide this most helpful answer. It is greatly appreciated.

Kind Regards,

Damien.