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  • java.sql.ResultSetMetaData.getColumnLabel和getColumnName的区别

    如果将ResultSet的结果映射到HashMap中,要使用getColumnLabel,而不要用getColumnName,这样可提高程序的健壮性

    理由:

    getColumnName返回的是sql语句中field的原始名字。
    getColumnLabel是field的SQL AS的值(Alias--别名)。
    比如:select
              a.name as name,
              a.description as description,
              b.description as relatedDescription
             from a,b where ...
    此时,getColumnName(3) == "description";而getColumnLabel(3) == "relatedDescription"。

    API:

    getColumnLabel

    String getColumnLabel(int column)
                          throws SQLException
    Gets the designated column's suggested title for use in printouts and displays. The suggested title is usually specified by the SQL AS clause. If a SQL AS is not specified, the value returned from getColumnLabel will be the same as the value returned by the getColumnName method.
    Parameters:
    column - the first column is 1, the second is 2, ...
    Returns:
    the suggested column title
    Throws:
    SQLException - if a database access error occurs

    getColumnName

    String getColumnName(int column)
                         throws SQLException
    Get the designated column's name.

     Parameters:

    column - the first column is 1, the second is 2, ...
    Returns:
    column name
    Throws:
    SQLException - if a database access error occurs

     

    http://blog.sina.com.cn/s/blog_735ef3790100qmf3.html 

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  • 原文地址:https://www.cnblogs.com/softidea/p/4094192.html
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