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