我使用的是隔离级别的Microsoft SQL Server 2005数据库READ_COMMITTED和READ_COMMITTED_SNAPSHOT=ON.
现在我想用:
SELECT * FROM <tablename> FOR UPDATE
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...以便在尝试访问同一行"FOR UPDATE"时阻止其他数据库连接.
我试过了:
SELECT * FROM <tablename> WITH (updlock) WHERE id=1
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...但是即使选择"1"以外的ID,这也会阻止所有其他连接.
SELECT FOR UPDATE对于Oracle,DB2,MySql而言,这是正确的提示吗?
编辑2009-10-03:
这些是创建表和索引的语句:
CREATE TABLE example ( Id BIGINT NOT NULL, TransactionId BIGINT,
Terminal BIGINT, Status SMALLINT );
ALTER TABLE example ADD CONSTRAINT index108 PRIMARY KEY ( Id )
CREATE INDEX I108_FkTerminal ON example ( Terminal )
CREATE INDEX I108_Key ON example ( TransactionId )
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很多并行进程都这样做SELECT:
SELECT * …Run Code Online (Sandbox Code Playgroud) sql t-sql sql-server sql-server-2005 read-committed-snapshot