11 2022 档案
摘要：group by select DepartmentID from BasicDepartment group by DepartmentID 注意： 在使用group by 时，有一个规则需要遵守，即出现在select列表中的字段，如果没有在组函数中，那么必须出现在group by 子句中。（se
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摘要：查重语句 select * from team where teamId in (select teamId from team group by teamId having count(teamId)> 1) select * from team where ID = 2 group by ID
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摘要：G_EMPLOYEE_POST select * from ORG_EMPLOYEE_POST as of timestamp to_Date('2021-11-15 13:50:00', 'yyyy-mm-dd hh24:mi:ss')
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摘要：alter session set nls_date_format = 'YYYY-MM-DD'; SELECT A.* FROM ORG_DEPT_INFO A LEFT JOIN ORG_INFO B ON A.ORG_ID = B.ID WHERE B.NAME LIKE '%达州%'; SE
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摘要：解决办法是，将select得到的结果，再通过中间表select一遍，这样就规避了错误，这个问题只出现于mysql，mssql和oracle不会出现此问题。 MySQL根据字段删除重复值 delete from sites where id not in ( select t.max_id from
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摘要：--创建数据库CREATE DATABASE DAY01_TEST01_MARKET; --创建表CREATE TABLE CUSTOMERS( C_NUM INT(11), C_NAME VARCHAR(50), C_CONTACT VARCHAR(50), C_CITY VARCHAR(50),
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