3)在表T上创建复合索引 sec@ora10g> create index t_i on t(x,y); Index created. 4)对表进行分析 sec@ora10g> analyze table t compute statistics; Table analyzed. 2.使用HINT方法使SQL走索引跳跃扫描 sec@ora10g> explain plan for select /*+ index_ss(t t_i) */ * from t where y=66; ...
pgsql 添加hint强制走索引 oracle使用强制索引 1、强制让oracle走索引 /*+INDEX(a CM_COOKIELOGINS_PK)*/ 其中a是表的别名,CM_COOKIELOGINS_PK是索引名称 2、oracle分区 oracle分区分为范围分区,列表分区以及hash分区,范围分区给定范围即可,列表分区需要列举出所有分区名称,hash分区则是对于不知道如何分区的表,给出...
The eq_range_index_dive_limit system variable enables you to configure the number of values at which the optimizer switches from one row estimation strategy to the other. To disable use of statistics and always use index dives, set eq_range_index_dive_limit to 0. To permit use of index d...
SqlIndexHint 屬性 C# 閱讀英文 儲存 新增至集合 新增至計劃 共用方式為 Facebookx.comLinkedIn電子郵件 列印 Reference Definition Namespace: Microsoft.SqlServer.Management.SqlParser.SqlCodeDom Assembly: Microsoft.SqlServer.Management.SqlParser.dll Package: ...
此时,我们就可以使用hint来改变SQL的join方式,impala的hint使用非常简单,如下所示: SELECT STRAIGHT_JOIN select_list FROM join_left_hand_table...的相应部分加入了STRAIGHT_JOIN和[shuffle]之后,SQL的执行计划就发生了改...
Prevents the query from using a nonclustered memory optimized columnstore index. If the query contains the query hint to avoid the use of the columnstore index, and an index hint to use a columnstore index, the hints are in conflict and the query returns an error. ...
WITH ( [ [ , ] ...n ] ) ::= { NOEXPAND | INDEX ( <index_value> [ , ...n ] ) | INDEX = ( <index_value> ) | FORCESEEK [ ( <index_value> ( <index_column_name> [ , ... ] ) ) ] | FORCESCAN | HOLDLOCK | NOLOCK | NOWAIT | PAGLOCK | READCOMMITTED | READCOMMI...
接下来我们将 4.0 TiDB 提供给用户的 SQL Hint 分五类分别介绍: 1. Table Hint Table Hint 控制优化器对查询中涉及的表所选择的访问方式,包括如下四种: USE_INDEX:让优化器对指定的表使用限定的索引进行访问,等价于 MySQL 语法中的use index() 。如果 USE_INDEX 中不指定索引部分的参数,表示...
USEHINT(<use_hint_name>[ , ...n ] ) |USEPLANN'<xml_plan>'|TABLEHINT(<exposed_object_name>[ ,[ [ , ] ...n ] ] ) |FORTIMESTAMPASOF'<point_in_time>'}::={NOEXPAND[ ,INDEX(<index_value>[ , ...n ] ) |INDEX= (<index_value>) ] |INDEX(<index_value>[ , ......
WITH([ [ , ] ...n ] )::={NOEXPAND|INDEX(<index_value>[ , ...n ] ) |INDEX= (<index_value>) |FORCESEEK[ (<index_value>(<index_column_name>[ , ... ] ) ) ] |FORCESCAN|HOLDLOCK|NOLOCK|NOWAIT|PAGLOCK|READCOMMITTED|READCOMMITTEDLOCK|READPAST|READUNCOMMITTED|REPEATABLEREAD|ROWLOCK...