2026-03-12 21:01:38

2026-03-12 22:01:38 +01:00
parent 3bd1db26cc
commit 26296b6d6a
336 changed files with 27507 additions and 0 deletions
--- a/partitioning/range_to_interval_03
+++ b/partitioning/range_to_interval_03
@@ -0,0 +1,131 @@
+drop table DEMO1 purge;
+
+create table DEMO1(
+	 id INTEGER generated always as identity
+	,day DATE not null
+	,code VARCHAR2(2) not null
+	,val NUMBER not null
+	,PRIMARY KEY(id)
+) 
+partition by range(day)(
+      partition P_2024_01 values less than (date'2024-02-01')
+     ,partition P_2024_02 values less than (date'2024-03-01')
+     ,partition P_2024_03 values less than (date'2024-04-01')
+     ,partition P_2024_04 values less than (date'2024-05-01')
+    )
+;
+
+create index IDX_VAL on DEMO1(val) local;
+
+insert /*+ APPEND */ into DEMO1 (day,code,val)
+select
+       DATE'2024-01-01' + trunc(DBMS_RANDOM.VALUE(1,30*4))
+      ,DECODE(trunc(DBMS_RANDOM.VALUE(1,10)),
+             1,  'UK'
+            ,2,  'UK'
+            ,3,  'UK'
+            ,4,  'UK'
+            ,5,  'UK'
+            ,6,  'IT'
+            ,7,  'IT'
+            ,8,  'FR'
+            ,9,  'FR'
+            ,10, 'FR'
+      )
+      ,trunc(DBMS_RANDOM.VALUE(1,10000))
+from 
+      xmltable('1 to 4000000')
+;
+commit;
+
+-- create a copy of the table
+
+drop table DEMO2 purge;
+
+create table DEMO2(
+       id INTEGER generated always as identity
+      ,day DATE not null
+      ,code VARCHAR2(2) not null
+      ,val NUMBER not null
+      ,PRIMARY KEY(id)
+) 
+partition by range(day)(
+      partition P_2024_01 values less than (date'2024-02-01')
+     ,partition P_2024_02 values less than (date'2024-03-01')
+     ,partition P_2024_03 values less than (date'2024-04-01')
+     ,partition P_2024_04 values less than (date'2024-05-01')
+    )
+;
+
+create index IDX_VAL2 on DEMO2(val) local;
+
+insert /*+ APPEND */ into DEMO2 (day,code,val) select day,code,val from DEMO1;
+commit;
+
+
+exec dbms_stats.gather_table_stats(user,'DEMO1');
+
+exec DBMS_STATS.SET_TABLE_PREFS(ownname=>'POC',tabname=>'DEMO2', pname=>'INCREMENTAL', pvalue=>'TRUE');
+exec DBMS_STATS.SET_TABLE_PREFS(ownname=>'POC',tabname=>'DEMO2', pname=>'GRANULARITY', pvalue=>'PARTITION');
+exec dbms_stats.gather_table_stats(user,'DEMO2');
+
+-- initial stats on DEM02 are faster because of incremental aggregation of GLOBAL stats instead basic calculation
+-- repeating gather table stats is much faster on DEMO2 (last_analyzed is nut increased)
+            (test if inserting a couple of lines in every partition change someting)
+
+
+-- convert tables to INTERVAL
+alter table DEMO1 set interval(NUMTOYMINTERVAL(1, 'MONTH'));
+alter table DEMO2 set interval(NUMTOYMINTERVAL(1, 'MONTH'));
+
+-- insert a lot of lines in 1-st partition
+drop table DEMOAUX purge;
+create table DEMOAUX as select * from DEMO1 where 1=0;
+alter table DEMOAUX drop column ID;
+
+insert /*+ APPEND */ into DEMOAUX (day,code,val)
+select
+       DATE'2024-01-01' + trunc(DBMS_RANDOM.VALUE(1,30*1))
+      ,DECODE(trunc(DBMS_RANDOM.VALUE(1,10)),
+             1,  'UK'
+            ,2,  'UK'
+            ,3,  'UK'
+            ,4,  'UK'
+            ,5,  'UK'
+            ,6,  'IT'
+            ,7,  'IT'
+            ,8,  'FR'
+            ,9,  'FR'
+            ,10, 'FR'
+      )
+      ,trunc(DBMS_RANDOM.VALUE(1,10000))
+from 
+      xmltable('1 to 1000000')
+;
+commit;
+
+
+insert /*+ APPEND */ into DEMO1 (day,code,val) select day,code,val from DEMOAUX;
+commit;
+
+insert /*+ APPEND */ into DEMO2 (day,code,val) select day,code,val from DEMOAUX;
+commit;
+
+
+-- stats on DEMO2 will be faster
+exec dbms_stats.gather_table_stats(user,'DEMO1');
+exec dbms_stats.gather_table_stats(user,'DEMO2');
+
+
+=> check why GLOBAL stats on DEMO2 are staled
+
+
+
+-- insert 1 line in a new partition
+insert into DEMO1 (day,code,val) values (date'2024-05-09','UK',1005);
+insert into DEMO2 (day,code,val) values (date'2024-05-09','UK',1005);
+commit;
+
+
+
+