IBM Db2 - The Ultimate Database for Cloud, Analytics & Mobile
A Db2 group buffer pool (GBP) consist of two parts:
1) Directory entries
2) Data entries
For each data entry there must be an associated directory entry in the GBP.
A directory entry can exist without a data entry in the…Continue
With APPLCOMPAT V12R1M504 on e.g. SPUFI or DSNTEP2, one can no longer create segmented or classic partitioned table spaces. See knowledge center for this restriction.
A small marginalia is behind this restriction, if this is combined with another…
One of the major challenges for RUNSTATS is the sampling of the data rows e.g. for calculation of the COLCARD value in SYSIBM.SYSCOLSTATS and SYSIBM.SYSCOLUMNS.
The challenge is to balance the CPU resources used by RUNSTATS to calculate column cardinalities with high accuracy…Continue
With DB2 Version 9.1 for z/OS a new system supplied stored procedure SYSPROC.ADMIN_INFO_SYSPARM was delivered. As the name suggests, this routine can be called to obtain the current settings of the Db2 subsystem parameters (DSNZPARM) and the…
Description of the new feature:
When Db2 in a data sharing environment writes a changed page to the GBP the same page in the buffer pool(s) of the other member(s) must be invalidated to avoid back level data access in this/these member(s). This invalidation is done by the cross invalidation (XI) feature which is a key functionality of data sharing and controlled by coupling facility…Continue
Added by Peter Hartmann on July 12, 2019 at 7:57 — No Comments