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USE tempdb
GO
IF OBJECT_ID('t1') IS NOT NULL DROP TABLE t1
IF OBJECT_ID('t2') IS NOT NULL DROP TABLE t2
IF OBJECT_ID('view_t') IS NOT NULL DROP VIEW view_t
GO
CREATE TABLE t1(
t1Id INT PRIMARY KEY,
t1Name NVARCHAR(10)
)
CREATE TABLE t2(
t2Id INT PRIMARY KEY,
t1Id INT,
t2Name NVARCHAR(10)
)
GO
INSERT INTO t1 (t1Id,t1Name)VALUES(1,'t1a')
INSERT INTO t2 (t2Id,t1Id,t2Name) VALUES (1,1,'t2a')
INSERT INTO t2 (t2Id,t1Id,t2Name) VALUES (2,1,'t2b')
GO
CREATE VIEW view_t
AS
SELECT t1.t1Id
,t1.t1Name
,t2.t2Id
,t2.t2Name
FROM t1 INNER JOIN t2 ON t1.t1Id=t2.t1Id
GO
SELECT * FROM view_t
/*
t1Id t1Name t2Id t2Name
----------- ---------- ----------- ----------
1 t1a 1 t2a
1 t1a 2 t2b
*/
--t1 表再插入一条数据
INSERT INTO t1 (t1Id,t1Name)VALUES(2,'t1b')
--再来看视图, 还是老样子, 条数没有增长
--因为 t2表 与 t1表 没有对应的记录
SELECT * FROM view_t
/*
t1Id t1Name t2Id t2Name
----------- ---------- ----------- ----------
1 t1a 1 t2a
1 t1a 2 t2b
*/