小编Mar*_*o G的帖子

我有这样的事情：

CREATE TABLE T1 (
    Id INT
    ...
    ,Constraint [PK_T1] PRIMARY KEY CLUSTERED [Id]
)

CREATE TABLE T2 (
    ....
    ,T1_Id INT NOT NULL
    ,CONSTRAINT [FK_T2_T1] FOREIGN KEY (T1_Id) REFERENCES T1(Id)
)

出于性能（和死锁）原因，我在 T1 上创建了一个新索引

CREATE UNIQUE NONCLUSTERED INDEX IX_T1_Id ON T1 (Id)

但是如果我检查哪个索引引用了 FK，就会继续引用聚集索引

select
    ix.index_id,
    ix.name as index_name,
    ix.type_desc as index_type_desc,
    fk.name as fk_name
from sys.indexes ix
    left join sys.foreign_keys fk on
        fk.referenced_object_id = ix.object_id
        and fk.key_index_id = ix.index_id
        and fk.parent_object_id = object_id('T2')
where ix.object_id = object_id('T1');

如果我删除约束并再次创建它引用非聚集索引，但这会导致再次检查所有 …