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Group functions
SELECT [column,] group_function(column) ... from table [WHERE condition] [GROUP BY group_by_expression] [ORDER BY column];
e.g.:
SELECT department_id, job_id, SUM(salary), COUNT(employee_id) from employees GROUP BY department_id, job_id ;
SELECT [column,] group_function(column).. ......
1. My test: (create and grant the sysdba to a new user by SQL*Plus)
CREATE USER FJTEST1 IDENTIFIED BY JEANJEANFANG;
GRANT SYSDBA TO FJTEST;
REVOKE SYSDBA from FJTEST;
CONNECT FJTEST1/JEANJEANFANG AS SYSDBA;
2. Using ORAPWD in windows:
C:\» ORAPWD;
(show help information)
3. to see th ......
in µÄ»°£¬ Èç¹ûÊÇnull ¾Í²»±È½ÏÁË£¬¼È²»ÊÇin Ò²²»ÊÇ not in
existsµÄ»° ÒòΪÓà = ¼ÓÔÚÌõ¼þÀï±È½ÏÁË£¬ËùÒÔ null ÊÇ not exists
select *
from pricetemp
where cast(ÉÌÆ·¥³ー¥É as varchar(10))not in(
select shohin_cd
&nbs ......
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EXEC sp_rename '±íÃû.[ÔÁÐÃû]', 'ÐÂÁÐÃû', 'column'
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sp_rename
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ÏÂÀý½«±í customers ÖØÃüÃûΪ custs¡£ ......
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if PATINDEX('%[ß¹-×ö]%','ÐèÒªÅжϵÄ×Ö·û')>0 -- ÅжÏÊÇ·ñÓÐ×Ö·û
print 'Óкº×Ö'
else
print 'ÎÞºº×Ö'
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