删除表中的所有唯一键 - T-SQL

Question

有没有一种方法可以从表中除掉主键除掉所有唯一键？

我的密钥名是由ORM生成的，我不能保证他们的名字。

Answer 1

试试这个

select 
    distinct 'Alter table MyTable drop constraint '+o.name 
from sys.objects o 
    join sys.columns c on o.parent_object_id = c.object_id AND o.type='UQ' 
    join sys.tables t on c.object_id = t.object_id 
where t.name = 'MyTable' 

Answer 2

这将删除所有的唯一约束，它不会丢弃主键。主键仍然会强制唯一性。

declare @table_name nvarchar(50) = 'yourtable' -- table 
declare @SchemaName nvarchar(50) = 'yourschema' -- dbo 
declare @Catalog nvarchar(50) = 'yourdatabase' -- database 

select * into #t from 
(
    select 'ALTER TABLE ' + TC.CONSTRAINT_CATALOG + '.' + TC.CONSTRAINT_SCHEMA + '.' + TC.TABLE_NAME + ' DROP CONSTRAINT ' + CCU.CONSTRAINT_NAME query 
    from INFORMATION_SCHEMA.TABLE_CONSTRAINTS as TC 
    inner join INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE as CCU 
    on TC.CONSTRAINT_CATALOG = CCU.CONSTRAINT_CATALOG 
    and TC.CONSTRAINT_SCHEMA = CCU.CONSTRAINT_SCHEMA 
    and TC.CONSTRAINT_NAME = CCU.CONSTRAINT_NAME 
    where TC.CONSTRAINT_CATALOG = coalesce(@Catalog, db_name()) 
    and TC.CONSTRAINT_SCHEMA = @SchemaName 
    and TC.TABLE_NAME = @table_name 
    and TC.CONSTRAINT_TYPE = 'UNIQUE' 
) a 

DECLARE @sqlstring as nvarchar(500) 
DECLARE SqlCursor CURSOR FAST_FORWARD FOR 
SELECT query FROM #t 
OPEN SqlCursor 
FETCH NEXT FROM SqlCursor 
INTO @sqlstring 
WHILE @@FETCH_STATUS = 0 
BEGIN 
exec(@sqlstring) 
    FETCH NEXT FROM SqlCursor 
    INTO @sqlstring 
END 
CLOSE SqlCursor 
DEALLOCATE SqlCursor 
DROP TABLE #t