(一)问题:数据库
最近在作Oracle数据清理,在对分区表进行数据清理时,采用的方法是drop partition,删除的过程当中,没有遇到任何问题,大概过了10分钟,开发人员反馈部分分区表上的业务失败。具体错误为:less
ORA-01502错误:索引或这类索引的分区处于不可用状态(英文:ora-01502:index 'schema.index_name' or partition of such index is in unusable state)。测试
(二)缘由分析ui
查看出现问题的分区表,均有一个共同点:表上以“pk_”开头的索引为unusable状态,以“pk_”开头的索引是随建立主键约束而建立的。当用户在建立主键约束或惟一性约束的时候,会在相应的列上建立惟一性索引spa
通过查证,发现是在删除分区的时候,致使分区表上的惟一性全局索引为不可用状态,致使新的数据没法正常插入,从而引起了该错误。设计
是否是索引不可用会致使DML操做失败呢?通过验证,发现如下特色:code
1.对于非惟一性索引,若是索引不可用,是不会影响到到DML操做的;对象
2.对于惟一性索引,若是索引不可用,在进行DML操做时,会触发ORA-01502错误;blog
这里记录一下哪些操做会致使索引失效:索引
图1.索引失效缘由总结
(三)解决方案
(3.1)了解惟一性索引
在解决问题以前,咱们来分析一下,哪些行为会建立惟一性索引(3种):
--直接建立惟一性索引。
语法为:CREATE UNIQUE INDEX index_name on table_name(col1,col2,…);
--建立主键约束时自动建立惟一性索引。
语法为:ALTER TABLE table_name ADD CONSTRAINT constraint_name PRIMARY KEY(col1,col2,..);
--建立惟一性约束时自动建立惟一性索引。
语法为:ALTER TABLE table_name ADD CONSTRAINT constraint_name UNIQUE(col1,col2,…);
这里,我总结了3套方案来对应ORA-01502问题。
(3.2)方案一:删除惟一性索引
与业务方面沟通,确认惟一性索引是否能够删除,若是能够,直接删除索引,删除语法为:
SQL> DROP INDEX schema.index_name;
对于由主键约束或惟一性约束建立的惟一性索引,不能直接删除
SQL> drop index lijiaman.sale_pk; drop index lijiaman.sale_pk ORA-02429: cannot drop index used for enforcement of unique/primary key
正确的方法是删除相应的约束。
SQL> alter table sales drop constraint sale_pk; Table altered
小结:该方法简单粗暴,前提是在约束或索引在业务方面能够删除的状况下才能使用。
(3.3)方案二:重建惟一性索引(针对非分区表)
语法为:
SQL> ALTER INDEX [schema.]index_name REBUILD [ONLINE] [TABLESPACE tablespace name]
小结:该方法可使索引可用。但对于分区表而言,依然存在问题:在下一次删除分区后,索引状态又会变为不可用。
(3.4)方案三:删除不可用的索引,建立惟一性分区索引(针对分区表)
建立惟一性分区索引:
SQL> CREATE UNIQUE INDEX index_name on [schema.]table(col1,col2,...);
对于主键约束、惟一性约束,可使用如下语法添加惟一性局部分区索引:
SQL> ALTER TABLE [schema.]table_name ADD CONSTRAINT constarint [PRIMARY KEY | UNIQUE](col1,col2) USING INDEX LOCAL TABLESPACE tablespace_name;
小结:该方法能够有效解决分区表因删除分区致使的索引不可用问题。
附录:模拟实验
(1)首先模拟生产状况,建立一张表:
create table sales ( prod_id number, cust_id number, time_id date, quantity_sold number(3) ) partition by range(time_id) ( partition sales_q1_2017 values less than(to_date('1-4-2017','dd-mm-yyyy')) , partition sales_q2_2017 values less than(to_date('1-7-2017','dd-mm-yyyy')) , partition sales_q3_2017 values less than(to_date('1-10-2017','dd-mm-yyyy')) , partition sales_q4_2017 values less than(to_date('1-1-2018','dd-mm-yyyy')) );
插入数据,确保每一个分区都有数据
insert into sales(prod_id,cust_id,time_id,quantity_sold)values(1,11,to_date('2017-02-01','yyyy-mm-dd'),103); insert into sales(prod_id,cust_id,time_id,quantity_sold)values(2,12,to_date('2017-06-01','yyyy-mm-dd'),103); insert into sales(prod_id,cust_id,time_id,quantity_sold)values(3,14,to_date('2017-08-01','yyyy-mm-dd'),103); insert into sales(prod_id,cust_id,time_id,quantity_sold)values(4,14,to_date('2017-12-01','yyyy-mm-dd'),103);
检查一下数据库的数据信息
SQL> select * from sales; --查看整个分区表的数据 PROD_ID CUST_ID TIME_ID QUANTITY_SOLD ---------- ---------- ----------- ------------- 1 11 2017/2/1 103 2 12 2017/6/1 103 3 14 2017/8/1 103 4 14 2017/12/1 103 SQL> select * from sales partition(sales_q1_2017); --查看分区“sales_q1_2017”的数据 PROD_ID CUST_ID TIME_ID QUANTITY_SOLD ---------- ---------- ----------- ------------- 1 11 2017/2/1 103
(2)因为出现ORA-01502问题时,与表相关的对象只有主键约束和索引。因此,我在表上建立了索引和约束,并确认了全部索引可用
alter table sales add constraint sale_pk primary key(time_id,cust_id); --建立主键约束 create index inx_sales_1 on sales(cust_id); --建立普通(全局)索引 create index inx_sales_2 on sales(time_id) local; --建立局部分区索引
确认索引状态:
SQL> select owner,table_name,index_name,status 2 from dba_indexes 3 where owner = 'LIJIAMAN' 4 and table_name = 'SALES'; OWNER TABLE_NAME INDEX_NAME STATUS ------------------------------ ------------------------------ ------------------------------ -------- LIJIAMAN SALES INX_SALES_2 N/A LIJIAMAN SALES SALE_PK VALID LIJIAMAN SALES INX_SALES_1 VALID
对于索引“SALES_PK”和“INX_SALES_1”,索引状态为可用,那”INX_SALES_2“这个索引状态为”N/A“,这又是怎么回事么?通过查找资料,确认索引共有四种状态:
咱们再去查看数据字典DBA_IND_PARTITIONS,确认”INX_SALES_2”的状态,索引可用。
SQL> SELECT INDEX_OWNER,INDEX_NAME,PARTITION_NAME,STATUS FROM DBA_IND_PARTITIONS I WHERE I.INDEX_OWNER = 'LIJIAMAN' AND I.INDEX_NAME = 'INX_SALES_2'; INDEX_OWNER INDEX_NAME PARTITION_NAME STATUS ------------------------------ ------------------------------ ------------------------------ -------- LIJIAMAN INX_SALES_2 SALES_Q1_2017 USABLE LIJIAMAN INX_SALES_2 SALES_Q2_2017 USABLE LIJIAMAN INX_SALES_2 SALES_Q3_2017 USABLE LIJIAMAN INX_SALES_2 SALES_Q4_2017 USABLE
确认主键约束的状态,确承认用
SQL> select owner,table_name,constraint_name,constraint_type,status,deferrable,deferred,validated 2 from dba_constraints 3 where owner = 'LIJIAMAN' 4 and table_name = 'SALES'; OWNER TABLE_NAME CONSTRAINT_NAME CONSTRAINT_TYPE STATUS DEFERRABLE DEFERRED VALIDATED --------- ------------ ----------------- --------------- -------- -------------- --------- ------------- LIJIAMAN SALES SALE_PK P ENABLED NOT DEFERRABLE IMMEDIATE VALIDATED
(3)接下来,咱们模拟数据清理,删除分区”sales_q1_2017“
SQL> alter table sales drop partition sales_q1_2017 ; Table altered
查看分区表的数据,能够看到,分区”sales_q1_2017“的数据已经随着分区被删除
SQL> select * from sales; PROD_ID CUST_ID TIME_ID QUANTITY_SOLD ---------- ---------- ----------- ------------- 2 12 2017/6/1 103 3 14 2017/8/1 103 4 14 2017/12/1 103
==================转折点==========================
(4)此时,咱们模拟正常的业务交易,发现以下状况
--对于insert操做,没法完成,报ORA-01502错误;
--对于delete操做,没法完成,报ORA-01502错误;
--对于update操做,若是不涉及到主键相关的列,则能够执行成功,若是涉及到主键列,报ORA-01502错误;
--数据插入测试,发现没法插入数据 SQL> insert into sales(prod_id,cust_id,time_id,quantity_sold)values(5,15,to_date('2017-8-01','yyyy-mm-dd'),103); insert into sales(prod_id,cust_id,time_id,quantity_sold)values(5,15,to_date('2017-8-01','yyyy-mm-dd'),103) ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state --数据删除测试,发现没法删除数据 SQL> delete from sales where prod_id = 3 ; delete from sales where prod_id = 3 ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state --数据跟新测试,测试3次,发现涉及到与主键相关的列,就会更新失败,其余状况更新成功 SQL> update sales set QUANTITY_SOLD = 105 where PROD_ID = 2; 1 row updated SQL> commit; Commit complete SQL> update sales set QUANTITY_SOLD = 105 where cust_id = 12; 1 row updated SQL> commit; Commit complete SQL> update sales set cust_id = 15 where PROD_ID = 2; update sales set cust_id = 15 where PROD_ID = 2 ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state
再次确认,索引的状态,能够看到,普通索引状态已经转变为不可用,而局部分区索引状态未发生改变。
SQL> select owner,table_name,index_name,status 2 from dba_indexes 3 where owner = 'LIJIAMAN' 4 and table_name = 'SALES'; OWNER TABLE_NAME INDEX_NAME STATUS ------------------------------ ------------------------------ ------------------------------ -------- LIJIAMAN SALES INX_SALES_2 N/A LIJIAMAN SALES SALE_PK UNUSABLE LIJIAMAN SALES INX_SALES_1 UNUSABLE SQL> SELECT INDEX_OWNER,INDEX_NAME,PARTITION_NAME,STATUS FROM DBA_IND_PARTITIONS I WHERE I.INDEX_OWNER = 'LIJIAMAN' AND I.INDEX_NAME = 'INX_SALES_2'; INDEX_OWNER INDEX_NAME PARTITION_NAME STATUS ------------------------------ ------------------------------ ------------------------------ -------- LIJIAMAN INX_SALES_2 SALES_Q2_2017 USABLE LIJIAMAN INX_SALES_2 SALES_Q3_2017 USABLE LIJIAMAN INX_SALES_2 SALES_Q4_2017 USABLE
主键约束状态也为发生改变
OWNER TABLE_NAME CONSTRAINT_NAME CONSTRAINT_TYPE STATUS DEFERRABLE DEFERRED VALIDATED ---------- ------------ ---------------- --------------- -------- -------------- --------- ------------- LIJIAMAN SALES SALE_PK P ENABLED NOT DEFERRABLE IMMEDIATE VALIDATED
这里,咱们对deop分区先后表的信息对比作一个小结
删除分区前 | 删除分区后 | |
查询(select) | 正常 | 正常 |
插入(insert) | 正常 | 没法插入 |
删除(delete) | 正常 | 没法删除 |
更新(update) | 正常 | 设计到主键相关的列,更新失败,其余状况更新成功 |
约束状态(constraint) | 可用 | 可用 |
索引状态(index) | 所有可用 | 1.分区索引可用 2.主键约束上的惟一性索引不可用 3.普通索引不可用 |
经过对比,咱们能够推测,索引不可用致使了没法正常DML操做。那么究竟是哪一个索引致使的问题呢?
(5)首先测试普通索引,先重建索引INX_SALES_1
SQL> alter index lijiaman.inx_sales_1 rebuild; Index altered SQL> select owner,table_name,index_name,status 2 from dba_indexes 3 where owner = 'LIJIAMAN' 4 and table_name = 'SALES'; OWNER TABLE_NAME INDEX_NAME STATUS ------------------------------ ------------------------------ ------------------------------ -------- LIJIAMAN SALES INX_SALES_2 N/A LIJIAMAN SALES SALE_PK UNUSABLE LIJIAMAN SALES INX_SALES_1 VALID
继续模拟DML交易,状况与删除分区后的DML结果相同,能够确认,普通索引不可用并不会引发DML操做失败
--数据依然没法插入 SQL> insert into sales(prod_id,cust_id,time_id,quantity_sold)values(5,15,to_date('2017-8-01','yyyy-mm-dd'),103); insert into sales(prod_id,cust_id,time_id,quantity_sold)values(5,15,to_date('2017-8-01','yyyy-mm-dd'),103) ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state --数据没法删除 SQL> delete from sales where prod_id = 3 ; delete from sales where prod_id = 3 ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state --若是没有更新到逐渐相关列,能够更新数据,不然不行 SQL> update sales set QUANTITY_SOLD = 105 where PROD_ID = 2; 1 row updated SQL> update sales set QUANTITY_SOLD = 105 where cust_id = 12; 1 row updated SQL> update sales set cust_id = 15 where PROD_ID = 2; update sales set cust_id = 15 where PROD_ID = 2 ORA-01502: index 'LIJIAMAN.SALE_PK' or partition of such index is in unusable state
(6)接着重建惟一性索引”SALE_PK”
SQL> alter index lijiaman.sale_pk rebuild; Index altered
对SALES表进行DML操做,能够正常进行
SQL> insert into sales(prod_id,cust_id,time_id,quantity_sold)values(5,15,to_date('2017-8-01','yyyy-mm-dd'),103); 1 row inserted SQL> delete from sales where prod_id = 3 ; 1 row deleted SQL> update sales set QUANTITY_SOLD = 105 where PROD_ID = 2; 1 row updated SQL> update sales set QUANTITY_SOLD = 105 where cust_id = 12; 1 row updated SQL> update sales set cust_id = 15 where PROD_ID = 2; 1 row updated SQL> commit; Commit complete
至此,咱们能够大胆猜想:惟一性索引致使的ORA-01502问题。因为咱们在建立索引的时候,并未直接建立惟一性索引,而是在建立主键约束的时候自动建立的惟一性索引,那么究竟是主键约束的问题,仍是惟一性索引的问题?根据上面删除分区先后约束状态相同,而索引状态不一样,我以为是索引的问题。继续求证。咱们新建一个表,在上面直接建立惟一性索引,不建立任何约束。
建立表test01,录入数据
SQL> select * from test01; ID NAME AGE ---------- -------------------- ---------- 1 lijiaman 2 gegeman 25 3 xiaoman 26 4 Lijiaman 25
在“ID”列建立惟一性索引
SQL> create unique index inx_test01 on test01(id); Index created SQL> select table_owner,index_name,index_type,uniqueness,status 2 from user_indexes 3 where table_name = 'TEST01'; TABLE_OWNER INDEX_NAME INDEX_TYPE UNIQUENESS STATUS ------------------------------ ------------------------------ --------------------------- ---------- -------- LIJIAMAN INX_TEST01 NORMAL UNIQUE VALID
插入数据,没有异常
SQL> insert into test01 values(5,'bokeyuan',22); 1 row inserted
接着将索引置为不可用状态,而后往表里面插入数据,出现了01502错误;
SQL> alter index lijiaman.inx_test01 unusable; --将索引置为不可用状态 Index altered SQL> select table_owner,index_name,index_type,uniqueness,status 2 from user_indexes 3 where table_name = 'TEST01'; TABLE_OWNER INDEX_NAME INDEX_TYPE UNIQUENESS STATUS ------------------------------ ------------------------------ --------------------------- ---------- -------- LIJIAMAN INX_TEST01 NORMAL UNIQUE UNUSABLE SQL> insert into test01 values(5,'bokeyuan',25); --插入数据,发生ORA-01502错误 insert into test01 values(5,'bokeyuan',25) ORA-01502: index 'LIJIAMAN.INX_TEST01' or partition of such index is in unusable state
至此能够明确的说:ORA-01512错误是因为惟一性索引失效致使的。
如何解决这个问题,前面给出了3种方案,只要选择其中一种便可,再也不模拟。