我有一个名为MemType的列的mysql数据库,此列将包含成员是否处于活动状态。并非所有成员都有效。我想计算活动成员并在textField中显示结果。我可以算一下,但不知道结果如何回来。我的代码如下:
@FXML
private void CountActionPerformed(ActionEvent event) {
String user = "root";
String password = "";
String ResultSet = null; // This is to ensure that ResultSet is empty.
try {
Connection myConn = DriverManager.getConnection("jdbc:mysql://localhost:3306/club", user, password);
System.out.println("Connection Successful ");
// Create statement.
Statement myStmt = myConn.createStatement();
ResultSet myRs = myStmt.executeQuery("SELECT COUNT(MemType)\n "
+ "FROM members \n "
+ "WHERE MemType = 'Active ' ");
while (myRs.next()) {
CountRel.setText(myRs.getString("MemType"));
}
} catch (Exception e) {
}
}
答案 0 :(得分:0)
您可以为列添加如下别名:
ResultSet myRs = myStmt.executeQuery("SELECT COUNT(MemType) as MemType "
+ "FROM members "
+ "WHERE MemType = 'Active ' ");
这应该是您需要的所有更改,您将只有一个结果(所有有效行的数量)
答案 1 :(得分:0)
结果是一个包含单列和单行的表。您可以使用列索引检索结果:
declare var jQuery: any;