时间:2021-07-01 10:21:17 帮助过:145人阅读
SELECT 索引名称=a.name
,表名=c.name
,索引字段名=d.name
,索引字段位置=d.colid
- FROM sysindexes a
- JOIN sysindexkeys b ON a.id=b.id AND a.indid=b.indid
- JOIN sysobjects c ON b.id=c.id
- JOIN syscolumns d ON b.id=d.id AND b.colid=d.colid
- WHERE a.indid NOT IN(0,255)
- -- and c.xtype='U' and c.status>0 --查所有用户表
- AND c.name='message' --查指定表
- ORDER BY c.name,a.name,d.name
需创建索引 例如:
根据某列判断是否有重复记录,如果该列为非主键,则创建索引
根据经常查询的列,创建索引
无须创建索引
字段内容大部分一样,例如:男,女
不要给所有的列都创建索引,这样在创建新记录时,增加维护开销时间。
Oracle 查询用户表索引
- select index_name,index_type,table_name from user_indexes where table_name='表名'
SqlServer查询一个表上的索引
- SELECT
- TableId=O.[object_id],
- TableName=O.Name,
- IndexId=ISNULL(KC.[object_id],IDX.index_id),
- IndexName=IDX.Name,
- IndexType=ISNULL(KC.type_desc,'Index'),
- Index_Column_id=IDXC.index_column_id,
- ColumnID=C.Column_id,
- ColumnName=C.Name,
- Sort=CASE INDEXKEY_PROPERTY(IDXC.[object_id],IDXC.index_id,IDXC.index_column_id,'IsDescending')
- WHEN 1 THEN 'DESC' WHEN 0 THEN 'ASC' ELSE '' END,
- PrimaryKey=CASE WHEN IDX.is_primary_key=1 THEN N'√'ELSE N'' END,
- [UQIQUE]=CASE WHEN IDX.is_unique=1 THEN N'√'ELSE N'' END,
- Ignore_dup_key=CASE WHEN IDX.ignore_dup_key=1 THEN N'√'ELSE N'' END,
- Disabled=CASE WHEN IDX.is_disabled=1 THEN N'√'ELSE N'' END,
- Fill_factor=IDX.fill_factor,
- Padded=CASE WHEN IDX.is_padded=1 THEN N'√'ELSE N'' END
- FROM sys.indexes IDX
- INNER JOIN sys.index_columns IDXC
- ON IDX.[object_id]=IDXC.[object_id]
- AND IDX.index_id=IDXC.index_id
- LEFT JOIN sys.key_constraints KC
- ON IDX.[object_id]=KC.[parent_object_id]
- AND IDX.index_id=KC.unique_index_id
- INNER JOIN sys.objects O
- ON O.[object_id]=IDX.[object_id]
- INNER JOIN sys.columns C
- ON O.[object_id]=C.[object_id]
- AND O.type='U'
- AND O.is_ms_shipped=0
- AND IDXC.Column_id=C.Column_id where O.name='cz201' --cz201是你要查询的表
以上内容就是本文全部所述,希望大家喜欢。