小编Hoo*_*igi的帖子

以下查询需要大约 10 秒才能在具有 12k 条记录的表上完成

select top (5) *
from "Physician"
where "id" = 1 or contains("lastName", '"a*"')

但是，如果我将 where 子句更改为

where "id" = 1

或者

where contains("lastName", '"a*"')

它会立即返回。

两列都被索引，lastName 列也被全文索引。

CREATE TABLE Physician
(
   id         int identity    NOT NULL,
   firstName  nvarchar(100)   NOT NULL,
   lastName   nvarchar(100)   NOT NULL
);

ALTER TABLE Physician
  ADD CONSTRAINT Physician_PK
  PRIMARY KEY CLUSTERED (id);

CREATE NONCLUSTERED INDEX Physician_IX2
   ON Physician (firstName ASC);

CREATE NONCLUSTERED INDEX Physician_IX3
   ON Physician (lastName ASC);

CREATE FULLTEXT INDEX
    ON …