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SQL学习

时间:2017-03-17 14:50:14      阅读:206      评论:0      收藏:0      [点我收藏+]

标签:order by   employee   delete   tail   int   limit   desc   not   sel   

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;

 

SQL学习

标签:order by   employee   delete   tail   int   limit   desc   not   sel   

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

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