Ich habe dazu eine kurze Nachricht in der Oracle Spatial and Graph Gruppe von LinkedIn geposted.
Das Ergebnis für 3 beispielhafte Queries kann sich mehr als sehen lassen. Die Zusammenfassung findet Ihr am Ende.
Für die Tests habe ich Beispieldaten (Postleitzahlgebiete von DE) des Oracle Partners GfK GeoMarketing verwendet. (Den anzupassenden Teil habe ich rot gekennzeichnet.)
REM spatial_12c_vpa_perf_test.sql - collect performance information related to Oracle Spatial 12c
REM Run script as user SYSTEM
define SRDCNAME='SPATIAL_VPA_PERF_TRACE'
set TERMOUT off FEEDBACK off VERIFY off TRIMSPOOL on HEADING off
COLUMN SRDCSPOOLNAME NOPRINT NEW_VALUE SRDCSPOOLNAME
select 'SRDC_'||upper('&&SRDCNAME')||'_'||upper(instance_name)||'_'||
to_char(sysdate,'YYYYMMDD_HH24MISS') SRDCSPOOLNAME from v$instance;
set TERMOUT on
REM
spool &&SRDCSPOOLNAME..txt
select '+----------------------------------------------------+' from dual
union all
select '| Diagnostic-Name: '||'&&SRDCNAME' from dual
union all
select '| Timestamp: '||
to_char(systimestamp,'YYYY-MM-DD HH24:MI:SS TZH:TZM') from dual
union all
select '| Machine: '||host_name from v$instance
union all
select '| Version: '||version from v$instance
union all
select '| DBName: '||name from v$database
union all
select '| Instance: '||instance_name from v$instance
union all
select '+----------------------------------------------------+' from dual
/
set HEADING on
set echo on feedback on termout on pages 999 lines 132 long 300000000
DEFINE OBJ_OWNER = &1
DEFINE OBJ_PASSWD = &2
/*
* Grant necessary privileges
*/
grant alter system to &&OBJ_OWNER;
grant alter session to &&OBJ_OWNER;
connect &&OBJ_OWNER/&&OBJ_PASSWD
alter system flush shared_pool;
alter session set tracefile_identifier='SRDC_Spatial_VPA_Perf_Test';
alter session set events '10046 trace name context forever, level 12';
-- alter session set sql_trace = TRUE;
alter session set spatial_vector_acceleration = FALSE;
set timing on
REM -- ------------------------------------
REM -- Add query to be traced and analyzed
REM -- Run without VPA first
REM -- ------------------------------------
REM -- Begin of query
with test as (
select sdo_aggr_union(sdoaggrtype(g.geometry,0.05)) aggr_geom
from de_5digpc_2010 g
where substr(g.id,1,1) in ('0','1','2'))
select count(*)
from test;
REM -- End of query
set timing off
alter system flush shared_pool;
alter session set spatial_vector_acceleration = TRUE;
set timing on
REM -- ------------------------------------
REM -- Add same query
REM -- Run with VPA now
REM -- ------------------------------------
REM -- Begin of query
with test as (
select sdo_aggr_union(sdoaggrtype(g.geometry,0.05)) aggr_geom
from de_5digpc_2010 g
where substr(g.id,1,1) in ('0','1','2'))
select count(*)
from test;
REM -- End of query
set timing off
spool off
Fazit:
Je grösser die Anzahl der zu aggregierenden Polygone, umso höher ist der Performancegwinn.
Und hier sind die Ergbnisse im Detail:
| Anzahl der aggr. Objekte | Geometrietyp | Elapsed time in Sek. ohne VPA | Elapsed time in Sek. mit VPA | Faktor | Abfrage |
|---|---|---|---|---|---|
| 10 | Polygon | 18,33 | 1,78 | 10 | with test as ( select sdo_aggr_union(sdoaggrtype(g.geometry,0.05)) aggr_geom from de_1digpc_2010 g) select count(*) from test; |
| 95 | Polygon | 151,66 | 2,44 | 62 | with test as ( select sdo_aggr_union(sdoaggrtype(g.geometry,0.05)) aggr_geom from de_2digpc_2010 g) select count(*) from test; |
| 2168 | Polygon | 1338,65 | 5,29 | 253 | with test as ( select sdo_aggr_union(sdoaggrtype(g.geometry,0.05)) aggr_geom from de_5digpc_2010 g where substr(g.id,1,1) in ('0','1','2')) select count(*) from test; |