oracle 如何从查询与结果集中获取单个值
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How to get a single value back from query vs resultset
提问by Baxter
I have a JSP file that runs a select statement against an Oracle database.
我有一个针对 Oracle 数据库运行选择语句的 JSP 文件。
All the examples I have seen use something like:
我见过的所有例子都使用类似的东西：
Statement st=connection.createStatement();
ResultSet rs=st.executeQuery("Select * from data");
while(rs.next(){
String name=rs.getString("name");
String add=rs.getString("address");
out.println(name+" "+add);
}
I will never have more than one row coming back is there an alternative to ResultSet and a while loop to get at my returning single row of data?
我永远不会返回多于一行 是否有替代 ResultSet 和 while 循环的方法来获取我返回的单行数据？
回答by Hardik Mishra
I have used similar kind of thing to validate user login.
我使用过类似的东西来验证用户登录。
String sql = "SELECT * FROM login WHERE username=? AND password=?";
try {
PreparedStatement statement;
statement = connection.prepareStatement(sql);
statement.setString(1, "hardik"); // set input parameter 1
statement.setString(2, "welcome"); // set input parameter 2
ResultSet rs = statement.executeQuery();
if(rs.next()){
// fetch data from resultset
}
}catch(SQLException sqle){
sqle.printStackTrace();
}
