Question

首先感谢那些曾帮助我的人。

我目前遇到的问题是这行代码

    statement.executeUpdate(myTableName);

或使用这些代码行

    String myTableName = "CREATE TABLE AgentDetail (" 
        + "idNo INT(64) NOT NULL AUTO_INCREMENT,"  
        + "initials VARCHAR(2)," 
        + "agentDate DATE,"  
        + "agentCount INT(64))";

当代码到达这些点时，它会生成一个由SQLException块捕获的错误。

它要么非常简单，要么非常复杂

有人可以指出这个Java MySQL编程的新手在哪里犯了错误，希望没有错误，提前谢谢

这是完整的其余代码

    public class DbStuff {
    private String jdbcDriver = "com.mysql.jdbc.Driver";
    private String dbAddress = "jdbc:mysql://localhost:3306/";
    private String userPass = "?user=root&password=";
    private String dbName = "TIGER19";
    private String userName = "root";
    private String password = "";

    private PreparedStatement preStatement;
    private Statement statement;
    private ResultSet result;
    private Connection con;

    public DbStuff() {
        try {
            Class.forName(jdbcDriver);
            con = DriverManager.getConnection(dbAddress + dbName, userName, password);
        } 
        catch (ClassNotFoundException e) {
            e.printStackTrace();
        } 
        catch (SQLException e) {
            createDatabase();
            createTableCub1();
        }
    }

    private void createDatabase() {
        try {
            Class.forName(jdbcDriver);
            con = DriverManager.getConnection(dbAddress + userPass);
            Statement s = con.createStatement();
            int myResult = s.executeUpdate("CREATE DATABASE IF NOT EXISTS " + dbName);
        } 
        catch (ClassNotFoundException | SQLException e) {
            e.printStackTrace();
        }
    }

    private void createTableCub1() {
        String myTableName = "CREATE TABLE AgentDetail (" 
            + "idNo INT(64) NOT NULL AUTO_INCREMENT,"  
            + "initials VARCHAR(2)," 
            + "agentDate DATE,"  
            + "agentCount INT(64))";  
        try {
            Class.forName(jdbcDriver);
            con = DriverManager.getConnection(dbAddress + dbName, userName, password);
            statement = con.createStatement();
            //The next line has the issue
            statement.executeUpdate(myTableName);
            System.out.println("Table Created");
        }
        catch (SQLException e ) {
            System.out.println("An error has occurred on Table Creation");
        }
        catch (ClassNotFoundException e) {
            System.out.println("An Mysql drivers were not found");
        }
    }
    }

Answer 1

首先感谢您的帮助和建议。这确实很有帮助。因此，我已经设法学习了三件事，

如何撰写有关如何创建表格的正确说明。
如何用Java创建MySQL表。
Smit所说的东西，就是阅读e.printStackTrace（）信息。

这是我提出的代码。

private void createTableCub1() {
    String myTableName = "CREATE TABLE AgentDetail (" 
            + "idNo INT(64) NOT NULL AUTO_INCREMENT,"  
            + "initials VARCHAR(2)," 
            + "agentDate DATE,"  
            + "agentCount INT(64), "
            + "PRIMARY KEY(idNo))";  
    try {
        Class.forName(jdbcDriver);
        con = DriverManager.getConnection(dbAddress + dbName, userName, password);
        statement = con.createStatement();
        //This line has the issue
        statement.executeUpdate(myTableName);
        System.out.println("Table Created");
    }
    catch (SQLException e ) {
        System.out.println("An error has occured on Table Creation");
        e.printStackTrace();
    }
    catch (ClassNotFoundException e) {
        System.out.println("An Mysql drivers were not found");
    }
}

当然，我欢迎并感谢任何和所有的反馈

Answer 2

您的表创建SQL语句不正确。要在mysql中设置列自动增量，它必须是主键。

CREATE TABLE AgentDetail ( 
        idNo INT(64) NOT NULL AUTO_INCREMENT, 
        initials VARCHAR(2),
        agentDate DATE,  
        agentCount INT(64),PRIMARY KEY (`idNo`));

Java在MySQL数据库中创建表

2 个答案: