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select * from tb_ai03
create table tb_ai031 as select * from tb_ai03
delete from tb_ai03 a where a.yymm in ('200911','200910')
insert into tb_ai03
select a.model,a.yysal/b.unitestrip as yysal ,a.mmsal/b.unitestrip as mmsal,
a.yychu/b.unitestrip as yychu,a.mmchu/b.unitestrip as mmchu,a.yymm
from tb_ld04 b,tb_ai031 a
where a.model=b.model(+) and a.yymm in ('200911','200910')
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What circumstances we use ALL_ROWS and what circumstances we use FIRST_ROWS optimizer mode? This article is written in oracle9i.
First_rows attempts to optimize the query to get the very first row back to the client as fast as possible. This is good for an interactive client server environment wher ......
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CREATE TABLE T(ID INTEGER);
CREATE VIEW V1 AS SELECT * from T;
CREATE VIEW V2 AS SELECT * from T WITH READ ONLY;
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INSERT INTO V1 VALUES(1);
--------------------
1 row cre ......
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