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  • SQL学习

    2017/2/13
    查询:
    SELECT * FROM c2_company;

    唯一值:
    SELECT DISTINCT company_type FROM c2_company;

    更精确的查找:
    SELECT * FROM c2_company c WHERE c.`COMPANY_NAME`='刘欢的de';

    AND:
    SELECT * FROM c2_company c WHERE c.`COMPANY_NAME`='刘欢的de' AND c.`COMPANY_TYPE`='T';

    OR:
    SELECT * FROM c2_company c WHERE c.`COMPANY_NAME`='刘欢的de' OR C.`COMPANY_TYPE`='R';

    ORDER BY 升序:
    SELECT * FROM c2_company ORDER BY parent_id;

    DESC 降序:
    SELECT * FROM c2_company ORDER BY parent_id DESC;

    UPDATE 修改:
    UPDATE c2_company SET company_name ='欢欢波波' WHERE company_name ='刘欢的de';

    DELETE 删除:
    DELETE FROM c2_company WHERE company_name='bobo';

    INSERT INTO 插入:
    INSERT INTO c2_company(id,company_name) VALUES (6,huanhuan);

    LIKE 模糊查询:
    SELECT * FROM c2_company WHERE company_name LIKE '欢%';
    SELECT * FROM c2_company WHERE company_name LIKE '%商';
    SELECT * FROM c2_company WHERE company_name LIKE '%小玩意%';
    SELECT * FROM c2_company WHERE company_name NOT LIKE '%小玩意%';

    TOP 摘取:
    SELECT top 5 * FROM c2_company;
    SELECT top 50 percent * FROM c2_comapny;

    MYSQL中语法 LIMIT :
    SELECT * FROM c2_company LIMIT 5;

    ORACLE中语法 :
    SELECT * FROM c2_company WHERE rownum <='6';

    IN 在where子句子中规定多个值:
    SELECT * FROM c2_company WHERE company_type IN ('T','R');

    BETWEEN ^ AND ^  选取这个范围内的值:
    SELECT * FROM c2_company WHERE id BETWEEN 2 AND 40;

    AS
    alias 别名:列
    SELECT id AS '排序',company_name AS'公司名称' FROM c2_company;

    JOIN 通过两个或多个表相同的部分,把表结合起来:
    通过两个表相同的部分进行结合:
    SELECT c2_company.`COMPANY_CODE`,c2_store.`BACK_NUMBER`FROM c2_company,c2_store
    WHERE c2_company.`AREA_ID_FK`=c2_store.`AREA_ID_FK`;

    INNER JOIN ^ ON 表中至少有一个匹配:
    SELECT c2_company.`COMPANY_CODE`,c2_store.`COUNTER_NUMBER` FROM c2_company INNER JOIN c2_store ON c2_company.`AREA_ID_FK`=c2_store.`AREA_ID_FK`;

    LEFT JOIN ^ ON 从左表有符合条件的行,即使右表没有符合条件的行。
    SELECT c2_company.`COMPANY_CODE`,c2_store.`COUNTER_NUMBER` FROM c2_company LEFT JOIN c2_store ON c2_company.`AREA_ID_FK`=c2_store.`AREA_ID_FK`;

    RIGHT JOIN ^ ON  从右表有符合条件的行,即使左表没有符合条件的行。
    SELECT c2_company.`COMPANY_CODE`,c2_store.`COUNTER_NUMBER` FROM c2_company RIGHT JOIN c2_store ON c2_company.`AREA_ID_FK`=c2_store.`AREA_ID_FK`;

    FULL JOIN ^ON  只要某个表存在匹配
    SELECT c2_company.`COMPANY_CODE`,c2_store.`COUNTER_NUMBER` FROM c2_company FULL JOIN c2_store ON c2_company.`AREA_ID_FK`=c2_store.`AREA_ID_FK`;

    UNION 合并两个或多个 SELECT 语句的结果集
    UNION 合并不重复:
    SELECT E_Name FROM Employees_China
    UNION
    SELECT E_Name FROM Employees_USA;

    UNION ALL 合并所有,会重复:
    SELECT E_Name FROM Employees_China
    UNION ALL
    SELECT E_Name FROM Employees_USA;

    SELECT * FROM c2_company;

    SQL函数
    AVG 平均值
    SELECT AVG(id) FROM c2_company;

    COUNT 统计数目
    SELECT COUNT(company_type) FROM c2_company WHERE company_type='T';
    SELECT COUNT(*) FROM c2_company;
    SELECT COUNT(DISTINCT company_type) FROM c2_company;

    FIRST 第一个值
    SELECT FIRST(id) FROM c2_company;

    LAST 最后一个值
    SELECT LAST(id) FROM c2_company;

    MAX 最大值
    SELECT MAX(id) FROM c2_company;

    MIN 最小值
    SELECT MIN(id) FROM c2_company;

    SUM 总和
    SELECT sum(id) FROM c2_company;

    -- 品牌商
    SELECT * FROM c2_brand

    -- 公司
    SELECT* FROM c2_company

    -- 零售商管理
    SELECT * FROM c2_retailer
     
    -- 门店
    SELECT * FROM c2_store

    -- 人员管理
    SELECT * FROM c2_user

     -- 门店人员关系表
    SELECT * FROM c2_store_user
     
    --
    SELECT * FROM c2_store c

    --  品顾表
    SELECT * FROM C2_SCAN_STOCK_CYCLE
        
     -- 收货地址
    SELECT c.* FROM c2_location_info c

    SELECT * FROM c2_goods c
    WHERE c.goods_name ='A8-930'
    AND c.color ='尊爵金(4+32GB版)_02';

    SELECT * FROM c2_company;

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  • 原文地址:https://www.cnblogs.com/liuhuanv/p/6565772.html
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