topic Re: ST05 - Need input in Application Development and Automation Discussions

ST05 - Need input

itabhishek9 — Mon, 27 Sep 2010 22:37:47 GMT

0 SELECT STATEMENT ( Estimated Costs = 8,976E+02 [timerons] ) num_rows tot_cost i/o_cost

1 RETURN 8.3011E02 8.9759E02 2.1266E+02

2 FETCH VBRP 8.3011E02 8.9759E02 2.1266E+02

3 RIDSCN 8.3011E02 3.9113E02 9.0109E+01

4 SORT 8.3011E02 3.9113E02 9.0109E+01

5 IXAND 8.3011E02 3.9066E02 9.0109E+01

6 IXSCAN VBRP~Z1 #key columns: 1 2.4903E03 1.2218E01 1.4210E+00

7 IXSCAN VBRP~0 #key columns: 1 3.1544E04 3.7651E02 8.8687E+01

This is the ST05 output when I press explain. Can someone please explain me how to interpret the same.

Regards,

Abhi

Re: ST05 - Need input

ravi_lanjewar — Tue, 28 Sep 2010 05:14:07 GMT

<< Cut and paste without attribution from http://abapreports.blogspot.com/2008_06_01_archive.html removed >>

Edited by: Rob Burbank on Sep 28, 2010 9:34 AM

Re: ST05 - Need input

HermannGahm — Tue, 28 Sep 2010 07:41:39 GMT

Hi,

DB6 "joins" your indexes VBRP_{0 and VBRP}Z1 with a logical AND.

This is called Index ANDing:

http://publib.boulder.ibm.com/infocenter/dzichelp/v2r2/index.jsp?topic=/com.ibm.db2tools.anl.doc.iug/anluc_multis.htm

http://publib.boulder.ibm.com/infocenter/db2luw/v9r5/index.jsp?topic=/com.ibm.db2.luw.admin.perf.doc/doc/c0024625.html

The intersection of the rowids for both index scans is used to access your table.

To judge whether this is efficient or not we would need additional data.... run time data, index and table definition, statistics and the statement...

Kind regars,

Hermann