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
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。