Conference rocks::dec_edi

3025.0. "V2.1C Audit Database indexes" by RULLE::KLASSON (Sven-Olof Klasson @GOO) Sat Feb 22 1997 18:29

Hi,

A customer noticed that we break our own recommendations in 
DECEDI$TOOLS:DECEDI$AUDIT_DATABASE.SQL for DEC/EDI V2.1C

The comments says not to store more then one sorted index in the same storage
area. A few lines down we do exactly that. Both indexes are for the same
table.

Does this have an impact on performance when sending/receiving large number
of OFTP transmissions?

Thanks,
Sven-Olof

.....
!   Create a misc storage area for each SORTED index. Do NOT store more than
!   one sorted index in the same storage area; especially for the same table.
!   This ensures that the index nodes for each index defined on the same table
!   will not be stored on the same page within the same storage area because
!   both indexes have the same logical area ID number.
.....
create storage area AUDIT.MISC_AREA_COMS_1
        filename DECEDI$AUDIT_DB_MISC_COMS_1
        page format is UNIFORM
        page size is 2 blocks
        allocation is 200 pages
        extent is 100 pages
.....
create unique index AUDIT.CLF_TRANSFILE_INDEX
        on AUDIT.CLF_TABLE ( TRNSFLE_S )
        type is SORTED
        store in MISC_AREA_COMS_1
.....
create unique index AUDIT.CLF_LOOKUP_INDEX
        on AUDIT.CLF_TABLE ( LOOKUP_S )
        type is SORTED
        store in MISC_AREA_COMS_1
.....

Hi Sven,

We'll "fix" that comment next time!

Mark

Just as an FYI: 

DEC/EDI  is based upon code that was written over a number of years by
people who have largely moved on to other jobs. In this case Raj and
Andy are long gone. I'm sure the reason for the comment was known at
the time, alas that knowledge walked out of the door with them.


Mark
  

.1> We'll "fix" that comment next time!

Please, fix the database instead; the comment is correct.
Pleeeeeease.