sql學習筆記

時間 2019-12-06

標籤 sql 學習筆記欄目 SQL 简体版

原文原文鏈接

按照id降序分組table

SELECT * FROM (SELECT * FROM zygh_standard_set WHERE DEL_FLAG=0 ORDER BY ROW_ID DESC) t GROUP BY COMPANY_ID,SOURCE_ID,GAME_ID變量

左聯（含瞬時變量）select

SELECT * FROM (SELECT SUM(IF(b.use_flag IS NOT NULL,1,0)) EMPLOYEE_SUM, SUM(IF(b.use_flag = 1,1,0)) EMPLOYEE_USING_SUM ,a.* FROM zygh_company a LEFT JOIN zygh_company_employee b ON a.row_id = b.company_id WHERE a.DEL_FLAG = 0 GROUP BY a.row_id)t ORDER BY CREATE_TIME DESCtab

插入（增長）co

INSERT INTO stu(sid,sname, sage) VALUES ('24','小王',25)ab

修改

UPDATE stu SET sage=？ WHERE sid=？

刪除

DELETE FROM stu WHERE sid=？

查

select *from table