java ojdbc 6 getInt() by column number返回错误的值

Question

我从ojdbc getInt()得到了一个非常有趣的列号错误。

ps = conn.prepareStatement("select count(*) from tableA");
rs = ps.executeQuery();
int x;
if (rs.next())
    x = rs.getInt(1);

ps = conn.prepareStatement("select count(*) as someVariable from tableA");
rs = ps.executeQuery();
int y;
if (rs.next())
    y = rs.getInt(1);

X和y的值不同。Y是我期望的正确数字。

我使用的是java 7和ojdbc6.jar (11.2.0.3.0)

谢谢。

Answer 1

ps = conn.prepareStatement("select count(*) as someVariable from tableA");
ps = conn.prepareStatement("select count(*) as result from tableA");
rs = ps.executeQuery();
int x;
if (rs.next())
    x = rs.getInt("result");

ps = conn.prepareStatement("select count(*) as someVariable from tableA");
rs = ps.executeQuery();
int y;
if (rs.next())
    y = rs.getInt("someVariable");

你没忘记rs.close()，conn.close()，statement.close()吗？使用资源进行尝试要比仅仅尝试要好。

try(Connection con = DriverManager.getConnection("DBpath","usr","pswd")) {
    //doSomething
}

在这种情况下，你不需要关闭它们，它们会自动关闭。注意:你只能用closeable对象来实现。