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  • 1 # 我是阿嘛

    1、建立測試表;

    create table company(companyId number, companyName varchar2(20), contacts varchar2(20));

    create table users(userId number, companyId number, userName varchar2(20), userAge number, address varchar2(20));

    2、插入測試資料;

    insert into company values (1,"騰訊科技","馬化騰");

    insert into company values (2,"微軟公司","鮑威爾");

    insert into company values (3,"新浪科技","小明" );

    insert into users values (1,1,"jack",23 , "上海");

    insert into users values (2,1,"jack2", 23, "上海");

    insert into users values (3,2,"jack3", 23, "上海");

    insert into users values (4,2,"jack4", 23, "上海");

    insert into users values (5,3,"jack5", 23, "上海");

    insert into users values (6,3,"jack6", 23, "上海");

    3、查詢表中資料;

    select * from users;

    4、編寫sql,關聯兩張表;select * from users t , company b where t.companyid = b.companyid and t.companyid = 1;

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