Laurent Vaills wrote:

> > > > > We are currently using the loadercli to migrate a 
> > > database to SAP DB.
> > > > > 
> > > > > We create the tables and all the indexes as they were 
> > > defined in the
> > > > > previous database.
> > > > > Then we run the loadercli to insert the values (with 
> the DATALOAD
> > > > > commands) in the defined tables.
> > > > > 
> > > > > Everything is ok, we got no error. But it seems that the 
> > > > > indexes are not
> > > > > updated : some queries take a very long time (> 1 hour) and 
> > > > > end up with
> > > > > "-904,Space for result tables exhausted". Our database is 
> > > created with
> > > > > 1Gb for the data devspace and is filled with only 14%.
> > > > > We tried to drop and recreate again the indexes and we 
> > > get the results
> > > > > of the queries in less than 1 minute.
> > > > > 
> > > > > After the DATALOAD commands, are there any special 
> > > commands to execute
> > > > > to update the index ? Why is it not done automatically ?
> > > > 
> > > > Indexes will be automatically updated by the SAP DB kernel 
> > > but I assume
> > > > the long runtime is the result of outdated optimizer statistics.
> > > > You should call the update statistics command for each 
> > > table after loading
> > > > data into it.
> > > 
> > > Is it a good advice to set up a cron job that updates the 
> statistics
> > > every night (like for PostgreSQL to run the command vacuumdb) ? 
> > 
> > A cron job for this purpose is a very good idea.
> > The frequency for that job depends on the change rate of the data.
> 
> My last (at least for today) question about sql_updatestat : 
> is it safe
> to execute that commands even if some users are updating or inserting
> the database ? (I do not want to reproduce the bug I got on 
> last friday
> with the "CREATE INDEX" while a user was inserting some data.)
> 
> I am using 7.4.3.27 .

It should be safe in general but I couldn't imagine what could happend 
if another error like the "CREATE INDEX" one occure.

Best regards,
Holger
SAP Labs Berlin

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