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  • 获得自动增长的MySQL主键

    下面的脚本教您如何获得自动增长的MySQL主键,如果您对MySQL主键方面感兴趣的话,不妨一看,相信对您学习MySQL主键方面会有所启迪。

    import java.sql.Connection;
    import java.sql.ResultSet;
    import java.sql.Statement;
    
    public class GetKey {
        ResultSet rs = null;
        Connection conn = null;
        Statement stmt = null;
        
        // 加入同一个连接发生其他查询,Key会被重写所以不准确
        public void getId() {
            try {
                Statement stmt = conn.createStatement();
                stmt.executeUpdate("insert into tb (name) values ('Key')");
                rs = stmt.executeQuery("SELECT LAST_INSERT_ID()");
                int autoIncKeyFromFunc = -1;
                if (rs.next()) {
                    autoIncKeyFromFunc = rs.getInt(1);
                    System.out.println("autoIncKeyFromFunc: " + autoIncKeyFromFunc);
                }
            } catch (Exception e) {
                System.out.print("有异常发生!");
            }
        }
        // getGeneratedKeys()是每次创建一个Statement 实例,所以是安全的!
        public void getId_() {
            try {
                stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_UPDATABLE);
                stmt.executeUpdate("insert into tb (name) values ('x')");
                int autoIncKeyFromApi = -1;
                rs = stmt.getGeneratedKeys();
                if (rs.next()) {
                    autoIncKeyFromApi = rs.getInt(1);
                    System.out.println("Key returned from getGeneratedKeys():" + autoIncKeyFromApi);
                }
            } catch (Exception e) {
                System.out.print("有异常发生!");
            }
        }
        public static void main(String[] args) {
            GetKey get = new GetKey();
            get.getId();
            get.getId_();
        }
    }
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  • 原文地址:https://www.cnblogs.com/opaljc/p/3357348.html
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