Question

我在两个不同的数据库Lab15DB_1和Lab15DB_2中有两个表。

父表是作者，子表是Book。

他们是：

CREATE TABLE Author 
(
    AuthorId INT NOT NULL PRIMARY KEY,
    AuthorName NVARCHAR(50) NOT NULL,
    AuthorSurname NVARCHAR(50) NOT NULL,
)

CREATE TABLE Book 
(
    BookId INT NOT NULL PRIMARY KEY,
    BookName NVARCHAR(50) NOT NULL,
    BookType NVARCHAR(50) NOT NULL CHECK(BookType IN ('Science', 'Hobby', 'Cooking', 'Fishing', 'Nature', 'Favorites')),
    PublishYear INT NOT NULL,
    AuthorId INT NOT NULL,
    Price MONEY CHECK (PRICE > 0.0)
)

我想通过触发器创建级联更新。

这是尝试在Author表上创建级联更新的触发器：

CREATE TRIGGER UpdateAuthorTrigger
ON Author 
FOR UPDATE
AS
    DECLARE @intRowCount int

    SELECT @intRowCount = @@ROWCOUNT

    IF @intRowCount > 1
    BEGIN
        IF UPDATE(AuthorId)
        BEGIN
            UPDATE Author 
            SET AuthorId = AuthorId
            /* some code for update Book*/
        END
    END
    ELSE
        IF @intRowCount = 1
        BEGIN
            IF UPDATE(AuthorId)
            BEGIN
                UPDATE Author
                SET Author.AuthorId = (SELECT AuthorId FROM INSERTED)
                FROM Author 
                INNER JOIN DELETED ON Author.AuthorId = DELETED.AuthorId

                UPDATE Lab15DB_1.dbo.Book
                SET Lab15DB_1.dbo.Book.AuthorId = (SELECT AuthorId FROM INSERTED)
                FROM Lab15DB_1.dbo.Book 
                INNER JOIN DELETED ON Lab15DB_1.dbo.Book.AuthorId = DELETED.AuthorId
            END
        END
GO

案例@intRowCount = 1没有问题，但案例@intRowCount > 1遇到了问题。

你能给我一些建议吗？

级联更新sql触发器

0 个答案: