Question

-- Database: `kanda`

-- Table structure for table `payments`
--

CREATE TABLE IF NOT EXISTS `payments` (
  `paymentId` int(11) NOT NULL AUTO_INCREMENT,
  `amount` double NOT NULL,
  `date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`paymentId`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=3 ;

--
-- Dumping data for table `payments`
--

INSERT INTO `payments` (`paymentId`, `amount`, `date`) VALUES
(1, 3000, '2015-01-13 08:47:46'),
(2, 3000, '2015-01-13 08:47:56');

-- phpMyAdmin SQL Dump
-- version 4.1.6
-- http://www.phpmyadmin.net
--
-- Host: 127.0.0.1
-- Generation Time: Jan 14, 2015 at 01:28 PM
-- Server version: 5.6.16
-- PHP Version: 5.5.9

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";


--


--
-- Table structure for table `schools`
--

CREATE TABLE IF NOT EXISTS `schools` (
  `schoolId` int(11) NOT NULL AUTO_INCREMENT,
  `paymentId` int(11) NOT NULL,
  `schoolname` varchar(20) NOT NULL,
  PRIMARY KEY (`schoolId`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=4 ;

--
-- Dumping data for table `schools`
--

INSERT INTO `schools` (`schoolId`, `paymentId`, `schoolname`) VALUES
(1, 1, 'westlands primary'),
(2, 2, 'st.johns primary');

Answer 1

使用：

SELECT * FROM schools INNER JOIN payments ON schools.schoolname = payments.amount;

您正在尝试将学校名称与金额相匹配，这将始终失败

尝试：

SELECT schools.name, payments.amount FROM schools INNER JOIN payments ON schools.paymentId = payments.paymentId;

我如何才能从付款和学校名称中提取金额？

1 个答案: