JDBC获得数据库生成的主键
在实际开发中，数据库中表的主键经常会由数据库负责生成，INSERT语句插入数据时插入除了主键以外的字段。很多情况下，当INSERT语句提交给数据库引擎执行完成后，程序需要获得生成的主键以便根据主键查询插入的记录。JDBC通过在调用语句对象的executeUpdate()
在实际开发中，数据库中表的主键经常会由数据库负责生成，INSERT语句插入数据时插入除了主键以外的字段。很多情况下，当INSERT语句提交给数据库引擎执行完成后，程序需要获得生成的主键以便根据主键查询插入的记录。JDBC通过在调用语句对象的executeUpdate()方法时，给出第二个参数Statement.RETURN_GENERATED_KEYS来说明希望数据库引擎返回生成的主键。生成的主键以结果集的形式返回，程序调用语句对象的getGeneratedKeys()方法得到一个结果集。遍历这个结果集，即得到数据库生成的主键。
全文请见：http://blog.csdn.net/microtong/archive/2009/12/08/4968041.aspx
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