标签:result ret cep sign val ash etc eth database
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:
String getColumnLabel(int column) throws SQLException
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.
column
- the first column is 1, the second is 2, ...SQLException
- if a database access error occurs
String getColumnName(int column) throws SQLException
Parameters:
column
- the first column is 1, the second is 2, ...SQLException
- if a database access error occursjava.sql.ResultSetMetaData.getColumnLabel和getColumnName的区别
标签:result ret cep sign val ash etc eth database
原文地址:http://www.cnblogs.com/keyi/p/6068675.html