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测试验证环境说明
测试用例说明
1、相同版本下,新增表数据量,使统计信息失效。优化器优先使用outline的计划。
2、相同版本下,绑定参数执行场景下,优化器优先使用outline的计划。
3、单机主备环境,优化器优先使用outline的计划。
4、升级数据库版本后,优化器优先使用outline的计划。
测试过程记录
点击查看代码
--建两张普通表test_tab1和test_tab2 并且分布插入200w数据。
create table test_tab1(col1 int, col2 int, col3 int);
create table test_tab2(col1 int, col2 int, col3 int);
SQL>
Succeed.
SQL>
Succeed.
SQL> begin
for i in 1..2000000 loop
insert into test_tab1 values(i+1,i+2,i+3);
insert into test_tab2 values(i+2,i+3,i+4);
end loop;
commit;
end;
/
PL/SQL Succeed.
-- 收集统计信息
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE);
PL/SQL Succeed.
--验证版本
SQL> select from v$version;
BANNER VERSION_NUMBER
---------------------------------------------------------------- -----------------
Release 22.2.10.100 x86_64 22.2.10.100
1 row fetched.
SQL> explain select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 29542( 0)| |
| 2 | TOP SORT DISTINCT | | | 1999998| 29538( 0)| |
| 3 | HASH JOIN INNER | | | 1999998| 24350( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 2000000| 453( 0)| |
| 5 | TABLE ACCESS FULL | TEST_TAB2 | SALES | 2000000| 453( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : access("T1"."COL2" = "T2"."COL2")
18 rows fetched.
SQL> create unique index idx1 on test_tab2(col2, col1);
Succeed.
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE);
PL/SQL Succeed.
-- 创建索引后,从HASH JOIN 转为NEXTED LOOPS INNER JOIN
SQL> explain select distinct t1.col1, t2.col1
2 from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
3
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 7785( 0)| |
| 2 | TOP SORT DISTINCT | | | 1999998| 7781( 0)| |
| 3 | NESTED LOOPS INNER | | | 1999998| 2594( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 2000000| 453( 0)| |
| 5 | INDEX RANGE SCAN | IDX1 | SALES | 1| 142( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
5 - Predicate : access("T2"."COL2" = "T1"."COL2")
18 rows fetched.
--删除索引后,执行计划从NEXTED LOOPS INNER 转为 HASH JOIN INNER
SQL> drop index IDX1;
Succeed.
SQL>
explain select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
SQL>
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 29542( 0)| |
| 2 | TOP SORT DISTINCT | | | 1999998| 29538( 0)| |
| 3 | HASH JOIN INNER | | | 1999998| 24350( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 2000000| 453( 0)| |
| 5 | TABLE ACCESS FULL | TEST_TAB2 | SALES | 2000000| 453( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : access("T1"."COL2" = "T2"."COL2")
18 rows fetched.
-- 创建索引前,增加outline
-- outline 分别是ol_ab和ol_a
SQL> CREATE OUTLINE ol_ab FOR CATEGORY ctgy_ab ON
select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
Succeed.
SQL> CREATE OUTLINE ol_a FOR CATEGORY ctgy_ab ON
select / + full(t2) / distinct t1.col1, t 2 3 4 2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
Succeed.
--应用outline,使得配置生效
SQL> ALTER SESSION SET USE_STORED_OUTLINES=ctgy_ab;
Succeed.
-- 整库收集统计信息,让执行计划重新生成
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE);
PL/SQL Succeed.
--创建索引
-- 经前面测试得知,创建索引后,此版本数据库会选择NEXTED LOOP JOIN
SQL> create unique index idx1 on test_tab2(col2, col1);
Succeed.
-- 可以看到outline已生效,依然走HASH JOIN INNER
SQL> explain select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
SQL>
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 29542( 0)| |
| 2 | TOP SORT DISTINCT | | | 1999998| 29538( 0)| |
| 3 | HASH JOIN INNER | | | 1999998| 24350( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 2000000| 453( 0)| |
| 5 | TABLE ACCESS FULL | TEST_TAB2 | SALES | 2000000| 453( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : access("T1"."COL2" = "T2"."COL2")
Outline Information :
---------------------------------------------------
- outline OL_AB used for this statement
23 rows fetched.
SQL> SELECT join_pos, hint
FROM USER_OUTLINE_HINTS
WHERE name = 'OL_AB'; 2 3
JOIN_POS HINT
-------- ----------------------------------------------------------------
0 LEADING(T1 T2)
0 USE_HASH(T2)
1 FULL(T1)
2 FULL(T2)
4 rows fetched.
持续新增200w数据,使得两张表统计信息失效
点击查看代码
begin
for i in 2000003 ..4000003 loop
insert into test_tab1 values(i+1,i+2,i+3);
insert into test_tab2 values(i+2,i+3,i+4);
end loop;
commit;
end;
/
此时统计信息已失效
点击查看代码
SQL> select from dba_tab_statistics where STALE_STATS!='N';
OWNER TABLE_NAME PARTITION_NAME PARTITION_POSITION SUBPARTITION_NAME SUBPARTITION_POSITION OBJECT_TYPE NUM_ROWS BLOCKS EMPTY_BLOCKS AVG_SPACE CHAIN_CNT AVG_ROW_LEN SAMPLE_SIZE LAST_ANALYZED GLOBAL_STATS USER_STATS LOCKED_STATS STALE_STATS SCOPE
---------------------------------------------------------------- ---------------------------------------------------------------- ---------------------------------------------------------------- --------------------- ----------------- --------------------- ------------- --------------------- --------------------- --------------------- ------------ --------------------- ------------ --------------------- -------------------------------- ------------ ---------- ------------ ----------- ---------
SALES TEST_TAB1 TABLE 2000000 6007 36 735 0 20 2000000 2024-08-07 Y N N Y SHARED
SALES TEST_TAB2 TABLE 2000000 6039 68 774 0 20 2000000 2024-08-07 Y N N Y SHARED
2 rows fetched.
统计信息失效后,优化器优先使用outline的计划
点击查看代码
-- outline 没有生效时,业务查询的计划
SQL> explain select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
2 3
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 943( 0)| |
| 2 | TOP SORT DISTINCT | | | 1000| 943( 0)| |
| 3 | NESTED LOOPS INNER | | | 100000| 683( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 100000| 442( 0)| |
| 5 | INDEX RANGE SCAN | IDX1 | SALES | 1| 142( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
5 - Predicate : access("T2"."COL2" = "T1"."COL2")
18 rows fetched.
--outline生效后,优化器优先使用outline的执行计划
SQL> ALTER SESSION SET USE_STORED_OUTLINES=ctgy_ab;
Succeed.
SQL> explain select distinct t1.col1, t2.col1
from test_tab1 t1 inner join test_tab2 t2 on t1.col2=t2.col2
order by t1.col1 limit 500;
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 2118027925
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 500| 29542( 0)| |
| 2 | TOP SORT DISTINCT | | | 1999998| 29538( 0)| |
| 3 | HASH JOIN INNER | | | 1999998| 24350( 0)| |
| 4 | TABLE ACCESS FULL | TEST_TAB1 | SALES | 2000000| 453( 0)| |
| 5 | TABLE ACCESS FULL | TEST_TAB2 | SALES | 2000000| 453( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : access("T1"."COL2" = "T2"."COL2")
Outline Information :
---------------------------------------------------
- outline OL_AB used for this statement
23 rows fetched.
绑定参数执行,优化器优先使用outline计划
点击查看代码
--创建绑定参数的outline CREATE OUTLINE ol_c FOR CATEGORY ctgy_ab ON select /*+ full(t2)*/ t2.col2,t2.col1 from test_tab2 t2 where t2.col2=? and t2.col1=?; Succeed. ALTER system SET USE_STORED_OUTLINES=ctgy_ab; -- outline生效 SQL> ALTER SESSION SET USE_STORED_OUTLINES=ctgy_ab; Succeed. SQL> explain select /*+ full(t2)*/ t2.col2,t2.col1 from test_tab2 t2 where t2.col2=? and t2.col1=?; PLAN_DESCRIPTION ---------------------------------------------------------------- SQL hash value: 631693285 Optimizer: ADOPT_C +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | 0 | SELECT STATEMENT | | | | | | |* 1 | TABLE ACCESS FULL | TEST_TAB2 | SALES | 1| 448( 0)| | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ Operation Information (identified by operation id): --------------------------------------------------- 1 - Predicate : filter("T2"."COL2" = Param(:0) AND "T2"."COL1" = Param(:1)) Hint Information : --------------------------------------------------- full(t2) / rejected by IGNORE_OPTIM_EMBEDDED_HINTS Outline Information : --------------------------------------------------- - outline OL_C used for this statement <details> <summary>点击查看代码</summary>
24 rows fetched.
AI 代码解读
单机主备架构下,outline功能测试
主备数据库都需要开启outline功能。
点击查看代码
[yashan@node01 install2210100]./bin/yasbootclusterstatus−cyashandb−dhostid|nodetype|nodeid|pid|instancestatus|databasestatus|databaserole|listenaddress|datapath−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−host0001|db|1−1:1|21925|open|normal|primary|192.168.33.103:1688|/home/yashan/yasdbdata/db−1−1+−−−−−−−−−−−+−−−−−−−−+−−−−−−−+−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−|db|1−2:2|21959|open|normal|standby|192.168.33.103:1690|/home/yashan/yasdbdata/db−1−2−−−−−−−−−−+−−−−−−−−−−−+−−−−−−−−+−−−−−−−+−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−−−−−+−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−[yashan@node01install2210100] yasql sys/yasdb_123@192.168.33.103:1688
YashanDB SQL Release 22.2.10.100 x86_64
Connected to:
YashanDB Server Release 22.2.10.100 x86_64 - X86 64bit Linux
SQL> ALTER SYSTEM SET USE_STORED_OUTLINES=ctgy_ab;
Succeed.
SQL> set autotrace on;
SQL> select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
COL2 COL1
---------------------------------------------------------------- ----------------------------------------------------------------
3 3
Execution Plan
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| Id | Operation type | Name | Owner | E - Rows | A - Rows | Cost(%CPU) | A - Time | Loops | Memory | Disk | Partition info |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | | | | | | |
| 1 | WINDOW | | | 1| | 2212( 0)| | | | | |
| 2 | SORT DISTINCT | | | 1| | 2212( 0)| | | | | |
| 3 | NESTED LOOPS INNER | | | 1| | 2212( 0)| | | | | |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| | 929( 0)| | | | | |
| 5 | INDEX FAST FULL SCAN | IDX_COL3 | SYS | 10000000| | 600( 0)| | | | | |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : filter("T2"."COL2" = "T3"."COL1")
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
Outline Information :
---------------------------------------------------
- outline OL_AF used for this statement
Statistics
----------------------------------------------------------------------------------------------------
25 rows fetched.
SQL>
Disconnected from:
YashanDB Server Release 22.2.10.100 x86_64 - X86 64bit Linux
--备库上测试outline功能
[yashan@node01 install2210100]$ yasql sys/yasdb_123@192.168.33.103:1690
YashanDB SQL Release 22.2.10.100 x86_64
Connected to:
YashanDB Server Release 22.2.10.100 x86_64 - X86 64bit Linux
SQL> set autotrace on;
SQL> select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
COL2 COL1
---------------------------------------------------------------- ----------------------------------------------------------------
3 3
Execution Plan
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| Id | Operation type | Name | Owner | E - Rows | A - Rows | Cost(%CPU) | A - Time | Loops | Memory | Disk | Partition info |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | | | | | | |
| 1 | WINDOW | | | 1| | 1071( 0)| | | | | |
| 2 | SORT DISTINCT | | | 1| | 1071( 0)| | | | | |
| 3 | NESTED LOOPS INNER | | | 1| | 1071( 0)| | | | | |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| | 929( 0)| | | | | |
| 5 | INDEX RANGE SCAN | IDX_COL3 | SYS | 1| | 142( 0)| | | | | |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
5 - Predicate : access("T3"."COL1" = "T2"."COL2")
Statistics
----------------------------------------------------------------------------------------------------
20 rows fetched.
--备库需要单独开启outline
SQL> ALTER SYSTEM SET USE_STORED_OUTLINES=ctgy_ab;
Succeed.
SQL> select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
COL2 COL1
---------------------------------------------------------------- ----------------------------------------------------------------
3 3
Execution Plan
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| Id | Operation type | Name | Owner | E - Rows | A - Rows | Cost(%CPU) | A - Time | Loops | Memory | Disk | Partition info |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | | | | | | |
| 1 | WINDOW | | | 1| | 2212( 0)| | | | | |
| 2 | SORT DISTINCT | | | 1| | 2212( 0)| | | | | |
| 3 | NESTED LOOPS INNER | | | 1| | 2212( 0)| | | | | |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| | 929( 0)| | | | | |
| 5 | INDEX FAST FULL SCAN | IDX_COL3 | SYS | 10000000| | 600( 0)| | | | | |
+----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : filter("T2"."COL2" = "T3"."COL1")
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
Outline Information :
---------------------------------------------------
- outline OL_AF used for this statement
Statistics
----------------------------------------------------------------------------------------------------
25 rows fetched.
升级数据库版本后,优化器优先使用outline为准
22.2.10.100 版本执行计划和创建outline al_af
点击查看代码
YashanDB Server Release 22.2.10.100 x86_64 - X86 64bit Linux
create table test_tab2(col1 varchar2(100),col2 varchar2(100),col3 varchar2(100));
create table test_tab3(col1 varchar2(100),col2 varchar2(100),col3 varchar2(100));
SQL>
Succeed.
Succeed.
SQL>
SQL>
begin
for i in 1..10000000 loop
insert into test_tab2 values(i+1,i+2,i+3);
insert into test_tab3 values(i+2,i+3,i+4);
end loop;
commit;
end;
/
SQL>
PL/SQL Succeed.
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE);
PL/SQL Succeed.
create index idx_col2 on test_tab2(col2);
create index idx_col3 on test_tab3(col1);
SQL>
Succeed.
SQL>
Succeed.
SQL> explain select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 1| 1071( 0)| |
| 2 | SORT DISTINCT | | | 1| 1071( 0)| |
| 3 | NESTED LOOPS INNER | | | 1| 1071( 0)| |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| 929( 0)| |
| 5 | INDEX RANGE SCAN | IDX_COL3 | SYS | 1| 142( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
5 - Predicate : access("T3"."COL1" = "T2"."COL2")
19 rows fetched.
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE);
PL/SQL Succeed.
SQL> explain select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 1| 1071( 0)| |
| 2 | SORT DISTINCT | | | 1| 1071( 0)| |
| 3 | NESTED LOOPS INNER | | | 1| 1071( 0)| |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| 929( 0)| |
| 5 | INDEX RANGE SCAN | IDX_COL3 | SYS | 1| 142( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
5 - Predicate : access("T3"."COL1" = "T2"."COL2")
19 rows fetched.
SQL> CREATE OUTLINE ol_af FOR CATEGORY ctgy_ab ON
select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
Succeed.
SQL>
ALTER SESSION SET USE_STORED_OUTLINES=ctgy_ab;
SQL>
Succeed.
SQL> explain select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1
where t2.col2 =3 limit 10;
PLAN_DESCRIPTION
----------------------------------------------------------------
SQL hash value: 4249347504
Optimizer: ADOPT_C
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
| 0 | SELECT STATEMENT | | | | | |
| 1 | WINDOW | | | 1| 2212( 0)| |
| 2 | SORT DISTINCT | | | 1| 2212( 0)| |
| 3 | NESTED LOOPS INNER | | | 1| 2212( 0)| |
| 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| 929( 0)| |
| 5 | INDEX FAST FULL SCAN | IDX_COL3 | SYS | 10000000| 600( 0)| |
+----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+
Operation Information (identified by operation id):
---------------------------------------------------
3 - Predicate : filter("T2"."COL2" = "T3"."COL1")
4 - Predicate : filter(CAST("T2"."COL2" AS NUMBER) = 3)
Outline Information :
---------------------------------------------------
- outline OL_AF used for this statement
24 rows fetched.
从22.2.10.100升级到23.2.3.100,同时开启outline,优化器优先使用outline存储执行计划
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SQL> select * from v$version; BANNER VERSION_NUMBER ---------------------------------------------------------------- ----------------- Enterprise Edition Release 23.2.3.100 x86_64 23.2.3.100 YashanDB Server Enterprise Edition Release 23.2.3.100 x86_64 - X86 64bit Linux SQL> explain select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1 where t2.col2 =3 limit 10; PLAN_DESCRIPTION ---------------------------------------------------------------- SQL hash value: 4249347504 Optimizer: ADOPT_C +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | 0 | SELECT STATEMENT | | | | | | | 1 | WINDOW | | | 1| 29( 0)| | | 2 | SORT DISTINCT | | | 1| 29( 0)| | | 3 | NESTED INDEX LOOPS INNER | | | 1| 29( 0)| | |* 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| 28( 0)| | |* 5 | INDEX RANGE SCAN | IDX_COL3 | SYS | 1| 1( 0)| | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ Operation Information (identified by operation id): --------------------------------------------------- 1 - Limit Expression: (LIMIT: 10) 2 - Distinct Expression: ("T2"."COL2") 4 - Predicate : filter("T2"."COL2" = 3) 5 - Predicate : access("T3"."COL1" = "T2"."COL2") 21 rows fetched. SQL> exec DBMS_STATS.GATHER_DATABASE_STATS('GATHER AUTO', 1, 16, 'FOR ALL COLUMNS SIZE AUTO', 'AUTO', TRUE, FALSE); SQL> PL/SQL Succeed. SQL> ALTER SESSION SET USE_STORED_OUTLINES=ctgy_ab; Succeed. SQL> explain select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1 where t2.col2 =3 limit 10; PLAN_DESCRIPTION ---------------------------------------------------------------- SQL hash value: 4249347504 Optimizer: ADOPT_C +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | Id | Operation type | Name | Owner | Rows | Cost(%CPU) | Partition info | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ | 0 | SELECT STATEMENT | | | | | | | 1 | WINDOW | | | 1| 767( 0)| | | 2 | SORT DISTINCT | | | 1| 767( 0)| | |* 3 | NESTED LOOPS INNER | | | 1| 767( 0)| | |* 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| 28( 0)| | | 5 | INDEX FAST FULL SCAN | IDX_COL3 | SYS | 10000000| 28( 0)| | +----+--------------------------------+----------------------+------------+----------+-------------+--------------------------------+ Operation Information (identified by operation id): --------------------------------------------------- 1 - Limit Expression: (LIMIT: 10) 2 - Distinct Expression: ("T2"."COL2") 3 - Predicate : filter("T2"."COL2" = "T3"."COL1") 4 - Predicate : filter("T2"."COL2" = 3) Outline Information : --------------------------------------------------- - outline OL_AF used for this statement 26 rows fetched. SQL> set autotrace on; SQL> select distinct t2.col2,t3.col1 from test_tab2 t2 inner join test_tab3 t3 on t2.col2=t3.col1 where t2.col2 =3 limit 10; 2 COL2 COL1 ---------------------------------------------------------------- ---------------------------------------------------------------- 3 3 Execution Plan ---------------------------------------------------------------- SQL hash value: 4249347504 Optimizer: ADOPT_C +----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+ | Id | Operation type | Name | Owner | E - Rows | A - Rows | Cost(%CPU) | A - Time | Loops | Memory | Disk | Partition info | +----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+ | 0 | SELECT STATEMENT | | | | | | | | | | | | 1 | WINDOW | | | 1| | 767( 0)| | | | | | | 2 | SORT DISTINCT | | | 1| | 767( 0)| | | | | | |* 3 | NESTED LOOPS INNER | | | 1| | 767( 0)| | | | | | |* 4 | INDEX FAST FULL SCAN | IDX_COL2 | SYS | 1| | 28( 0)| | | | | | | 5 | INDEX FAST FULL SCAN | IDX_COL3 | SYS | 10000000| | 28( 0)| | | | | | +----+--------------------------------+----------------------+------------+----------+----------+-------------+----------+----------+----------+----------+--------------------------------+ Operation Information (identified by operation id): --------------------------------------------------- 1 - Limit Expression: (LIMIT: 10) 2 - Distinct Expression: ("T2"."COL2") 3 - Predicate : filter("T2"."COL2" = "T3"."COL1") 4 - Predicate : filter("T2"."COL2" = 3) Outline Information : --------------------------------------------------- - outline OL_AF used for this statement Statistics ---------------------------------------------------------------------------------------------------- 27 rows fetched.