如何利用觸發(fā)器實現(xiàn)兩個數(shù)據(jù)庫間的同步

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若對于同一數(shù)據(jù)庫實例中的兩個數(shù)據(jù)庫進行同步則直接對數(shù)據(jù)庫表創(chuàng)建Trigger。
    SQL Server 2005的聯(lián)機幫助:
    Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger)
    CREATE TRIGGER [ schema_name . ]trigger_name
    ON { table | view }
    [ WITH [ ,...n ] ]
    { FOR | AFTER | INSTEAD OF } { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] }
    [ WITH APPEND ]
    [ NOT FOR REPLICATION ]
    AS { sql_statement [ ; ] [ ...n ] | EXTERNAL NAME }
    ::= [ ENCRYPTION ] [ EXECUTE AS Clause ]
    ::= assembly_name.class_name.method_name
    以下是一個例子
    set ANSI_NULLS ON
    set QUOTED_IDENTIFIER ON
    go
    -- =============================================
    -- Author: gsoosg
    -- Create date: 2007-12-24
    -- Description:
    -- =============================================
    CREATE TRIGGER [Trigger_Add_Carduser]
    ON [dbo].[carduser]
    AFTER INSERT
    AS
    BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;
    set insert ParkFee.dbo.card_user(card_user_id,card_user_name,sex)
    select card_user_id,card_user_name,sex from inserted
    END
    說明:
    上例實現(xiàn)了為當(dāng)前數(shù)據(jù)庫中表carduser創(chuàng)建觸發(fā)器當(dāng)插入數(shù)據(jù)時,同步向ParkFee數(shù)據(jù)庫表dbo.card_user插入數(shù)據(jù),從而達到同步插入。類同,可將insert語句改為update,delete。
    注意:
    若想利用此方法達到反向同步則可能出現(xiàn)問題,比如想在parkfee數(shù)據(jù)庫有新數(shù)據(jù)插入時讓當(dāng)前數(shù)據(jù)庫也同時插入一條記錄,建立一個觸發(fā)器,則形成了一個循環(huán)觸發(fā),當(dāng)插入數(shù)據(jù)時會報大于遞歸次數(shù)錯。因此因避免這樣的觸發(fā)循環(huán),若要達到類似效果還須想別的方法。(待續(xù))
    補充:
    若兩個庫處于不同的數(shù)據(jù)庫服務(wù)器則應(yīng)先進行以下操作:
    在 server1 上創(chuàng)建連接服務(wù)器,以便在 server1 中操作 server2,實現(xiàn)同步
    exec sp_addlinkedserver 'server2','','SQLOLEDB','server2的數(shù)據(jù)庫實例名或ip'
    exec sp_addlinkedsrvlogin 'server2','false',null,'用戶名','密碼'
    go