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  • SQL语法

    CREATE TABLE student(stuName VARCHAR(30),carId CHAR(7),carPrice INT);studentstudent;
    //使用SQL添加数据
    INSERT INTO student(stuName,stuAge,stuAddr)VALUES('小冷','16','北京');
    INSERT INTO student VALUES('小小','15','燕京');
    INSERT INTO student(stuName,stuAge)VALUES('小海','17');
    //WHERE 限定条件
    DELETE FROM student WHERE stuAddr='吉林'AND stuAge>19;
    DELETE FROM student WHERE stuAddr='长春'OR stuAge=16;
    //单字段修改
    UPDATE student SET stuAge='25'WHERE stuAddr='北京';
    //多字段修改  用逗号分隔
    UPDATE student SET stuAge='30',stuAddr='燕京'WHERE stuName='小红';
    //查询
    SELECT stuName,stuAge FROM student WHERE stuAddr='北京';
    //升序排列
    SELECT stuName ,stuAge FROM student ORDER BY stuAge ASC;
    //降序排列
    SELECT stuName,stuAge FROM student ORDER BY stuAge DESC;
    //取出前3条记录,第一个参数表示从哪开始(下标),第二个参数表示取出的个数
    SELECT stuName,stuAge,stuAddr FROM car LIMIT 0,3;
    //取出第二个到第四个
    SELECT stuName,stuAge,stuAddr FROM car LIMIT 1,3;
    //去除重复数据
    SELECT DISTINCT stuAge FROM car
    //分组数据
    //统计男女各有多少人
    SELECT stuSex,COUNT (*)FROM car GROUP BY stuSex;

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  • 原文地址:https://www.cnblogs.com/tytr/p/5897134.html
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