We use it because you can determine runstats by schema and not just
tabname.  So you can do a reorgchk on a certain schema, which will
runstat all tables in the schema, whereas if you do runstats alone,
then you need to do it table by table.

ROERGCHK is a utility to determine if a table needs to be REORG'ed

However you usualy want to make that determination using updated
statistics.  So "REORGCHK UPDATE STATISTICS ON TABLE ALL" runs a
RUNSTATS on the table before running the REORGCHK utility on it.

REORGCHK, on its own, does nothing to optimize a table, as stated above,
its a utility to determine if a table needs to be REORG'ed based on the
current statistics.

Hope this helps.

Christos

When REORGCHK calls runstats, it simply does "RUNSTATS on table".

If you want distribution statistics and/or detailed index stats,
like statistics, etc. you need to use RUNSTATS directly (and then
execute REORGCHK separately).

The main difference is as follows:
REORGCHK will run the stats on on or more tables, in the same way they were
last run.
This means if you ran with distribution statisitics and detailed indexes it
will also run the stats in that way from the REORGCHK command.  Note that
you cannot specify that in the reorgchk command.

Doing a runstats command will pick up the stats in the way you specify in
the command, with or without distribution and detailed indexes.
It also resets those options so that if you run REORGCHK it will run the
stats as specified in the last way you ran them.

HTH,  Pierre.