- create view
ORACLE: CREATE OR REPLACE VIEW V_FA_ADD_CO AS
SQLSEVER: IF EXISTS (SELECT 1
FROM sysobjects
WHERE idobject_id ('V_FA_ADD_CO')
AND type = 'V')
DROP VIEW V_FA_ADD_CO;
CREATE VIEW V_FA_ADD_CO AS
2. the equal between join and (+)
the table(its fields stay with (+)) right join another corresponding table.
for example: select * from a,b where a.id=b.id(+)
equals select * from b rigth join a on a.id=b.id
equals select * from a left join a on a.id=b.id
notes:join先匹配有对应的记录,
(+)却是按顺序来的
3. substr,substring
for example: there is a table's field "userName" and it's value is "wanghuiling".
sqlserver: substring(userName,0,4) = "wan",substring(userName,1,4) = "wang"
oracle: substr(userName,0,4)="wang",substr(userName,1,4)="wang"
4. link sign
sqlserver: "+"
oracle:"||"
5. update a table's some fields
for example:there are two tables: students1 and students2
sqlserver:update students (can't use alias)
set name=s2.name,sex=s2.sex,age=s2.age,tel=s2.tel
from students s2 where s1.id=s2.id;
oracle: update students1 s1
set (name,sex,age,tel)=
(select name,sex,age,tel from students2 s2 where s1.id=s2.id);
6. Date
for example:there are a field of date type:input_date and its value is 2007-08-09.
sqlserver : year(input_date)=2007,month(input_date)=8,day(input_date)=9
oracle : to_char(input_date,'YYYY')=2007, to_char(input_date,'MM')=8, to_char(input_date,'DD')=9
sDate : a java String variable
sqlserver : input_date = '"+sDate+"'
oracle : input_date = to_char( '" + sDate + "',' 'YYYY-MM-DD'')
posted on 2006-12-31 15:42
freefly 阅读(562)
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