CREATE INDEX i ON t (a,b,c) REVERSE; 例2:使一个索引变为反向键索引: ALTER INDEX i REBUILD NOREVERSE; §3.6.3 索引组织表 与普通的索引不一样,索引组织表(Index_Organized Table)是根据表来存储数据,即将索引和表存储在一起。这样的索引结构表(Index_organized table—IOT)的特点是:对表数据的改变,...
(XMLIndex_parameters_clauseについては、『Oracle XML DB開発者ガイド』を参照してください。) local_XMLIndex_clause::= 図「local_xmlindex_clause.gif」の説明 global_partitioned_index::= 図「global_partitioned_index.gif」の説明 (index_partitioning_clause::=、individual_hash_partitions::=、hash_...
But first, let’s delve into the different types of indexes available in Oracle Database.How to Choose the Index TypeOracle Database offers many different types of index to improve your SQL. One of the key decisions you need to make is whether to go with a bitmap or B-tree index....
Oracle Database Concepts for a discussion of indexes Oracle Database Reference for more information about the limits related to index size ALTER INDEX and DROP INDEX Prerequisites To create an index in your own schema, one of the following conditions must be true: The table or cluster to...
百度试题 结果1 题目在Oracle 中, CREATE INDEX语句用来创建( )。( 选择一项) A. 序列 B. 同义词 C. 索引 D. 视图 相关知识点: 试题来源: 解析 C 反馈 收藏
Oracle Database - Enterprise Edition - Version 11.2.0.3 and later: How to calculate the number of columns in a create index statement giving ORA-01793: Maximum Numbe
PostgreSQL, Oracle DROPINDEXcollege_index; MySQL ALTERTABLECollegesDROPINDEXcollege_index; Here, the SQL command removes an index namedcollege_indexfrom theCollegestable. Note:Deleting an index in SQL means only the index is deleted. The data in the original table remains unaltered. ...
In a concurrent index build, the index is actually entered as an“invalid” index into the system catalogs in one transaction, then two table scans occur in two more transactions. Before each table scan, the index build must wait for existing transactions that have modified the table to termin...
The Oracle administrator configures the database; the geodatabase administrator creates the geodatabase To create a geodatabase in an Oracle database, you run a geoprocessing tool or Python script from an ArcGIS client. Start by reading the prerequisites, then follow the instructions that apply ...
pgtt is a PostgreSQL extension to create, manage and use Oracle-style Global Temporary Tables and the others RDBMS. The objective of this extension it to provide the Global Temporary Table feature to PostgreSQL waiting for an in core implementation. The main interest of this extension is to mim...