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

java.sql.ResultSetMetaData.getColumnLabel和getColumnName的区别