(By default, Oracle Database creates B-tree indexes.) Bitmap indexes, which store rowids associated with a key value as a bitmap. Partitioned indexes, which consist of partitions containing an entry for each
One more parameter used in the CREATE INDEX statement is COMPUTE STATISTICS. It is an optional parameter telling Oracle to collect the statistics during index creation. Further, this stats data would serve when choosing the “plan of execution” of SQL statements. However, since Oracle 10, the ...
Oracle Database ConceptsandOracle Data Warehousing Guidefor more information about logging and parallel DML "Creating an Index in NOLOGGING Mode: Example" ONLINE SpecifyONLINEto indicate that DML operations on the table will be allowed during creation of the index. Restrictions on Online Index Buildin...
online indexbuild (online create或者rebuild index)是Oracle的一个极其常用的online操作,我们知道当创建索引或者重建索引没有加online关键字的话,会请求表对象上的4号TM锁,而DML请求的是3号TM锁,3和4的TM锁并不兼容,所以在索引创建或者重建期间是无法进行DML操作的,等待事件为enq: TM – contention。 为了改进这...
5、如果不想并行创建索引,去掉parallel参数,或者指定parallel=1即可。 参考文档:Impdp Parallel Index Creation always creates indexes with degree 1. (Doc ID 1289032.1) Bug 8604502 : INDEXES ARE ALWAYS CREATED WITH PARALLEL DEGREE 1 DURING IMPORT
online index build(online create或者rebuild index)是Oracle的一个非常常用的online操作,我们知道当创建索引或者重建索引没有加online关键字的话,会请求表对象上的4号TM锁,而DML请求的是3号TM锁,3和4的TM锁并不兼容,所以在索引创建或者重建期间是无法进行DML操作的,等待事...
Oracle Database - Enterprise Edition - Version 11.2.0.4 and later: ORA-1427 Attaching to Job Stopped During the Index Creation in Order to Restart It
online index build(online create或者rebuild index)是Oracle的一个非常常用的online操作,我们知道当创建索引或者重建索引没有加online关键字的话,会请求表对象上的4号TM锁,而DML请求的是3号TM锁,3和4的TM锁并不兼容,所以在索引创建或者重建期间是无法进行DML操作的,等待事件为enq: TM – contention。
--Oracle 自动创建了索引并关联到约束, 索引名和约束名是相同的。 --验证下索引 SYS@anqing2(rac2)> selectindex_name,index_type,uniqueness,generated from user_indexes wheretable_name='UT'; INDEX_NAME INDEX_TYPE UNIQUENES GENERATED --- --- --- UC_PHONE NORMAL UNIQUE N --我们并没有创建索引,...
--Oracle 自动创建了索引并关联到约束, 索引名和约束名是相同的。 --验证下索引 SYS@anqing2(rac2)> selectindex_name,index_type,uniqueness,generated from user_indexes wheretable_name='UT'; INDEX_NAME INDEX_TYPE UNIQUENES GENERATED --- --- --- UC_PHONE NORMAL UNIQUE N --我们并没有创建索引,...