(no subject)

uunet.uu.net!rhlab!kuhn writes >Here is a bit of performance information I would like to pass on. > > Platform: 3B2/400 Unix V 3.1 >OLD Informix: 2.10.03K >NEW Informix: 4.0 > >In running the query described below on my OLD version performance was >completely acceptable. On version 4.0, ouch!!!! Queries that took seconds >were now taking lots........ of minutes like 15,20,25 minutes. stuff deleted to your tables, i added an index on each for ptype,pno informix tech support has verified for me that if you only select data which is defined in your keys, the data segment is not read. you should save the data read on pinfo this way. also the selects are now all though indexes. please advise me if you test this on what happens to your 4.0 query time. thanks, kathy QUERY: from 4.0 INFORMIX with explain on: ------ select caseno, pn.pno, pname, pn.ptype from pinfo,pn where pn.ptype = "M" and pn.ptype = pinfo.ptype and pn.pno = pinfo.pno and pname matches "ANDERSON,K*"; Estimated Cost: 9 Estimated # of Rows Returned: 4 1) root.pinfo: INDEX PATH (1) Index Keys: pname Lower Index Filter: root.pinfo.pname MATCHES 'ANDERSON,K*' 2) root.pn: INDEX PATH Filters: (root.pn.ptype = root.pinfo.ptype AND root.pn.ptype = 'M' ) (1) Index Keys: pno Lower Index Filter: root.pn.pno = root.pinfo.pno