Joshua D. Drake wrote: > Kai Hessing wrote: >> 1.) 21.5 seconds >> 2.) 363.7 seconds >> >> But it is still a significant difference. > > Can you provide an explain analyze of each query? There isn't an explain analyze of the first variant, because there are just 2000 SQL-Updates. The explain analyze for just one of the commands (UPDATE xyz SET status=-6 WHERE phon='xyz1' AND status>-1;) is: ------------------ Index Scan using phon_phon_idx on phon (cost=0.00..5193.83 rows=530 width=148) (actual time=0.146..0.146 rows=0 loops=1) Index Cond: ((phon)::text = 'xyz'::text) Filter: (status > -1) Total runtime: 0.387 ms 1 Datensätze (means data sets) Laufzeit gesamt: 16.682 ms (means running time) ------------------ The second one (UPDATE xyz WHERE id IN (xyz1, xyz2, ....) AND status>-1;) returns: ------------------ Seq Scan on phon (cost=0.00..1573304.58 rows=105931 width=148) (actual time=369563.565..369563.565 rows=0 loops=1) Filter: ((((phon)::text = 'xyz1) OR ((phon)::text = 'xyz2'::text) OR ((phon)::text = 'xyz3'::text) OR ((phon)::text = 'xyz4'::text) OR ... [all the 2000 entries from the IN clause] Total runtime: 369566.954 ms 667 Datensätze (means data sets) Laufzeit gesamt: 370,179.246 ms (means running time) ------------------ Hope, that helps. Have a nice weekend. Being back to work on monday ;) *greets* Kai
