从非聚簇更改主键聚集

Question

假设我有一个SQL Server 2005的表，TableX的，与2个指标就可以了：

PK_TableX = PRIMARY KEY NONCLUSTERED上FIELDA
IX_TableX_FieldB =聚集在FieldB

我想将PK切换为CLUSTERED，而另一个索引是NONCLUSTERED。

我不得不假设数据库将在我尝试更改索引轮的时刻使用 - 所以我主要关心的是我想要避免的是在该进程中的某个点PK约束不会存在在桌子上。我想要防止重复键被插入的风险。

即我不能放弃主键并重新创建它。

此过程需要通过SQL脚本完成，而不是通过SSMS。

我有一个我认为可行的方法（我会将它作为潜在答案发布），但是想要打开它以防万一我失去了某些东西或者有其他更好的方法。另外，它可以证明是有用的人，将来

Answer 1

1）删除现有的聚集索引第一（IX_TableX_FieldB）：

DROP INDEX TableX.IX_TableX_FieldB 

2）创建上所引用的唯一字段（临时）唯一约束主键

ALTER TABLE TableX 
    ADD CONSTRAINT UQ_TableX UNIQUE(FieldA) 

3）删除该PRIMARY KEY

ALTER TABLE TableX 
    DROP CONSTRAINT PK_TableX 

4 ）重新将主键CLUSTERED

ALTER TABLE TableX 
    ADD CONSTRAINT PK_TableX PRIMARY KEY CLUSTERED(FieldA) 

5）删除临时UNIQUE约束

ALTER TABLE TableX 
    DROP CONSTRAINT UQ_TableX 

6）添加IX_TableX_FieldB回为NONCLUSTERED

CREATE NONCLUSTERED INDEX IX_TableX_FieldB ON TableX(FieldB) 

Answer 2

我知道这是旧的，但这将编写出所有FK掉落，PK掉落，pk重新创建，FK重新创建。 用你的表名替换MYTABLE。

IF EXISTS (SELECT * FROM sys.tables WHERE object_id = OBJECT_ID(N'[dbo].[FKAgainstTableList]')) 
BEGIN 
    DROP TABLE FKAgainstTableList 
END 
--CREATE TABLE FKAgainstTableList (ForeignKey VARCHAR(30),[Table] VARCHAR(30)) 
DECLARE @PKTableName VARCHAR(100), 
     @PKName varchar(100), 
     @FKName varchar(100), 
     @sql varchar(max), 
     @PKcolumnName varchar(30), 
     @table VARCHAR(100), 
     @FKColumnName VARCHAR(100), 
     @parentColumnNumber int 
SET @PKTableName = 'MYTABLE' 
set @PKName = (SELECT name FROM sys.indexes WHERE OBJECT_NAME(object_id) = @PKTableName AND is_primary_key = 1) 
set @PKcolumnName = (SELECT name FROM sys.columns WHERE OBJECT_NAME(object_id) = @PKTableName AND is_identity =1) 
PRINT @PKcolumnName 

SELECT OBJECT_NAME(sys.foreign_key_columns.parent_object_id) [Table],sys.columns.name [FKColumnName],sys.foreign_keys.name [FKName] 
    INTO FKAgainstTableList 
    FROM sys.foreign_keys INNER JOIN sys.foreign_key_columns 
    ON sys.foreign_keys.object_id = sys.foreign_key_columns.constraint_object_id 
    INNER JOIN sys.columns ON sys.columns.object_id = sys.foreign_keys.parent_object_id AND sys.columns.column_id = sys.foreign_key_columns.parent_column_id 
    WHERE OBJECT_NAME(sys.foreign_keys.referenced_object_id) = @PKTableName 


DECLARE table_cur1 CURSOR FOR 
    SELECT * FROM FKAgainstTableList 

    PRINT @sql 

-------------------------------Disable constraint on FK Tables 
OPEN table_cur1 
FETCH NEXT FROM table_cur1 INTO @table,@FKColumnName,@FKName 
WHILE @@FETCH_STATUS = 0 
    BEGIN 
     SET @sql ='ALTER TABLE '+@table+' DROP CONSTRAINT '+ @FKName 
     PRINT @sql 
     FETCH NEXT FROM table_cur1 INTO @table,@FKColumnName,@FKName 
    END 
CLOSE table_cur1 
DEALLOCATE table_cur1 
--------------------------------DROP AND recreate CLUSTERED pk 
IF EXISTS (SELECT 1 FROM sys.indexes WHERE object_id = OBJECT_ID(@PKTableName) AND name = @PKName) 
BEGIN 
    SET @sql = 'ALTER TABLE '+@PKTableName+' DROP CONSTRAINT '+ @PKName 
    PRINT @sql 

END 
SET @sql = 'ALTER TABLE '+@PKTableName +' ADD CONSTRAINT '+@PKName+' PRIMARY KEY CLUSTERED ('+@PKcolumnName+' ASC) 
WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 80) ON [PRIMARY]' 
PRINT(@sql) 

--------------------------------Enable FK constraints on FK tables. 
DECLARE table_cur2 CURSOR FOR 
    SELECT * FROM FKAgainstTableList 
OPEN table_cur2 
FETCH NEXT FROM table_cur2 INTO @table,@FKColumnName,@FKName 
WHILE @@FETCH_STATUS = 0 
    BEGIN 
     SET @sql = 'ALTER TABLE '+@table+' WITH NOCHECK ADD CONSTRAINT '+ @FKName+' FOREIGN KEY(['+@FKColumnName+']) 
     REFERENCES ['+@PKTableName+'] (['+@PKcolumnName+'])' 
     PRINT(@sql) 
     SET @sql = 'ALTER TABLE '+@table+' CHECK CONSTRAINT '+@FKName 
     PRINT(@sql) 

     FETCH NEXT FROM table_cur2 INTO @table,@FKColumnName,@FKName 

     END 
CLOSE table_cur2 
DEALLOCATE table_cur2 
DROP TABLE FKAgainstTableList