ORA-01652，temp表空间不足的相关问题及处理
十一长假期间也不得轻松，某日接到业务保障，数据库报错，导致某关键业务不能正常执行，需要立即处理
原因分析
1，登录数据库，查看主机日志，报错内容为ORA-01652，temp表空间不足
ORA-01652: unable to extend temp segment by 128 in tablespace TEMP01
2，让业务部门重新执行相关脚本，发现占用temp表空间的具体语句如下，目前temp表空间96GB，大约1个小时会被该sql使用满，sql异常退出
Sql具体如下
INSERT INTO www.WWW_BILL_DTL_TEMP_0101(ACCT_ID,SERV_ID,FEE,BRAND,
PHONE_ID,USER_TYPE) SELECT ACCT_ID, SERV_ID, sum(FEE) FEE,BRAND
,PHONE_ID,USER_TYPE FROM ( SELECT ACCT_ID, SERV_ID, SUM(FEE) F
EE,BRAND,PHONE_ID,USER_TYPE FROM (select a.acct_id,e.serv_id,s
um(b.unpay_fee) FEE,a.brand,a.phone_id,a.user_type from www.ACC_B
ILL_010120121010 A , www.WWW_BILL_DTL_010120121010 B , www.OWE_MO
NITOR_QUEUE_ACTION E where a.bill_id=b.bill_id and A.ACCT_ID=E.
ACCT_ID and a.brand in (:"SYS_B_00",:"SYS_B_01",:"SYS_B_02",:"SY
S_B_03",:"SYS_B_04",:"SYS_B_05") and b.fee_item_id>:"SYS_B_06"
group by a.acct_id,e.serv_id,a.brand,a.phone_id,a.user_type ) g
roup by ACCT_ID, SERV_ID,BRAND,PHONE_ID,USER_TYPE UNION ALL SE
LECT ACCT_ID, SERV_ID, -:"SYS_B_07"*SUM(FEE) FEE,BRAND,PHONE_ID,
USER_TYPE FROM (select a.acct_id,e.serv_id,sum(b.unpay_fee) FE
E,a.brand,a.phone_id,a.user_type from www.WWW_BILL_010120121005 A
, www.WWW_BILL_DTL_010120121005 B , www.WWW_MONITOR_QUEUE_ACTION
E where a.bill_id=b.bill_id and A.ACCT_ID=E.ACCT_ID and a.bran
d in (:"SYS_B_08",:"SYS_B_09",:"SYS_B_10",:"SYS_B_11",:"SYS_B_12
",:"SYS_B_13") and b.fee_item_id>:"SYS_B_14" group by a.acct_id
,e.serv_id,a.brand,a.phone_id,a.user_type ) group by ACCT_ID, S
ERV_ID,BRAND,PHONE_ID,USER_TYPE ) GROUP BY ACCT_ID, SERV_ID,BRAN
D,PHONE_ID,USER_TYPE执行计划如下
Plan hash value: 3236377944
--------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------------------------------------------------
| 0 | INSERT STATEMENT | | | | 19281 (100)| |
| 1 | HASH GROUP BY | | 2 | 184 | 19281 (2)| 00:03:52 |
| 2 | VIEW | | 2 | 184 | 19280 (2)| 00:03:52 |
| 3 | UNION-ALL | | | | | |
| 4 | SORT GROUP BY | | 1 | 92 | 19271 (2)| 00:03:52 |
| 5 | VIEW | | 1 | 92 | 19271 (2)| 00:03:52 |
| 6 | SORT GROUP BY | | 1 | 144 | 19271 (2)| 00:03:52 |
|* 7 | HASH JOIN | | 1 | 144 | 19270 (2)| 00:03:52 |
| 8 | MERGE JOIN CARTESIAN | | 1 | 65 | 8717 (2)| 00:01:45 |
| 9 | TABLE ACCESS FULL | WWW_MONITOR_QUEUE_ACTION | 1 | 26 | 2 (0)| 00:00:01 |
| 10 | BUFFER SORT | | 257K| 9810K| 8715 (2)| 00:01:45 |
|* 11 | TABLE ACCESS FULL | WWW_BILL_DTL_010120121010 | 257K| 9810K| 8715 (2)| 00:01:45 |
|* 12 | TABLE ACCESS FULL | WWW_BILL_010120121010 | 16755 | 1292K| 10552 (1)| 00:02:07 |
| 13 | SORT GROUP BY | | 1 | 53 | 9 (12)| 00:00:01 |
| 14 | VIEW | | 1 | 53 | 9 (12)| 00:00:01 |
| 15 | SORT GROUP BY | | 1 | 79 | 9 (12)| 00:00:01 |
| 16 | TABLE ACCESS BY INDEX ROWID | WWW_BILL_DTL_010120121005 | 1 | 18 | 3 (0)| 00:00:01 |
| 17 | NESTED LOOPS | | 1 | 79 | 8 (0)| 00:00:01 |
| 18 | NESTED LOOPS | | 1 | 61 | 5 (0)| 00:00:01 |
| 19 | TABLE ACCESS FULL | WWW_MONITOR_QUEUE_ACTION | 1 | 26 | 2 (0)| 00:00:01 |
|* 20 | TABLE ACCESS BY INDEX ROWID| WWW_BILL_010120121005 | 1 | 35 | 3 (0)| 00:00:01 |
|* 21 | INDEX RANGE SCAN | ITDX_ACCT_ID_10120121005 | 1 | | 2 (0)| 00:00:01 |
|* 22 | INDEX RANGE SCAN | TPK_BILL_DTL_ID_10120121005 | 1 | | 2 (0)| 00:00:01 |
--------------------------------------------------------------------------------------------------------------------3，继续分析原因。仔细分析该sql语句，实际上可以拆分为两个并列子sql。后一部分的sql执行计划是好的，不优的是上半部分，因此解决方案就很简单了，把上半部分的统计信息和索引做成和下半部分同样的结构。经查确认，上部分的sql缺少相关索引，且由于表今天创建，且插入了大量数据，且没有统计信息，选择列没有设置索引，导致执行计划不优。
SQL> select * from dba_objects where object_name ='WWW_BILL_DTL_010120121010';
OWNER OBJECT_NAME SUBOBJECT_NAME
------------------------------ -------------------------------------------------------------------------------------------------------------------------------- ------------------------------
OBJECT_ID DATA_OBJECT_ID OBJECT_TYPE CREATED LAST_DDL_TIM TIMESTAMP STATUS T G S
---------- -------------- ------------------- ------------ ------------ ------------------- ------- - - -
ZC WWW_BILL_DTL_010120121010
1209877 1209877 TABLE 06-OCT-12 06-OCT-12 2012-10-06:11:19:25 VALID N N N解决方法
1，表WWW_BILL_DTL选择列ACCT_ID，在表WWW_BILL上bill_id，FEE_ITEM_ID添加组合索引，
2，然后重新收集统计信息，sql即走合适的执行路径了
exec dbms_stats.gather_table_stats('ZC',WWW_BILL_DTL_010120121010,method_opt => 'FOR ALL COLUMNS SIZE 1',cascade =>TRUE,estimate_percent => 40,granularity=>'all',degree => 4,no_invalidate => false);
exec dbms_stats.gather_table_stats('ZC',WWW_BILL_010120121010,method_opt => 'FOR ALL COLUMNS SIZE 1',cascade =>TRUE,estimate_percent => 40,granularity=>'all',degree => 4,no_invalidate => false)简单总结：
1，本次问题出在新建的临时表，没有同时新建相关索引，且在数据创建和大量数据插入后，没有立即收集统计信息，导致oracle无法选择合适的执行计划，进而占用大量临时表空间，sql无法正常执行完成。
2，merge join cartesian（笛卡儿算法）：是每个集合的任务一个成员都要与其他集合的每个成员进行匹配。因此原有执行计划需要执行对两个大表的N×N次查询和排序，占用大量temp表空间