Dear colleagues,
Our warehouse fact table receives approximately four million inserts per day. Current RUNSTATS executes weekly via a scheduled utility job. We are observing suboptimal access paths on queries filtering by BUSINESS_DATE after the third day post-RUNSTATS.
Sample utility control card:
jcl
//STEP1 EXEC PGM=DSNUTILB,REGION=0M
//STEPLIB DD DSN=DB2.RUNLIB.LOAD,DISP=SHR
//SYSIN DD *
RUNSTATS TABLESPACE DSNDB04.FACTTS
TABLE(WAREHOUSE.SALES_FACT)
SHRLEVEL CHANGE
UPDATE ALL
/*
IBM documentation notes:
Would you increase RUNSTATS frequency, move to STOSPACE-based triggers, or adopt real-time statistics if licensed? I am particularly interested in how you quantify "stale enough to matter."SHRLEVEL CHANGE allows concurrent DML during RUNSTATS but may produce statistics that reflect an intermediate state.
Regards,
Elena