Oracle系列之三----Implicit Cursor
Oracle系列之一----Datatype And Subprogram：http://overshit.iteye.com/admin/blogs/932585；
Oracle系列之二----Exception And Expression：http://overshit.iteye.com/admin/blogs/932605；
Oracle系列之三----Implicit Cursor：http://overshit.iteye.com/admin/blogs/932609；
Oracle系列之四----Dynamic Cursor：http://overshit.iteye.com/admin/blogs/932610；
Oracle系列之五----Cursor And Variable：http://overshit.iteye.com/admin/blogs/932612；
Oracle系列之六----Procedure--Package--Purity：http://overshit.iteye.com/admin/blogs/932615；
Oracle系列之七----Trigger：http://overshit.iteye.com/admin/blogs/932616；
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----implicit cursor:sql%notfound returning----sql%isopen/*Attribute:sql%found:a value of boolean,if influence records in db,it returns true,or return false; sql%notfound:against sql%found; sql%rowcount:how many records are influenced(return an integer); sql%isopen:a value of boolean,if cursor is open,return true,or return fase,implicit cursor always return fasle; Method:returning: lay back result of sql expression operation,reduce access db query operation,upgrade db performance;*/drop table temp;create table temp( tid varchar2(10), tname varchar2(20))insert into temp values ('1','meilin');insert into temp values ('2','bing');insert into temp values ('3','qing');declarev_temp temp%rowtype;begin update temp set tname = 'syntax' where tid = 1 returning tid,tname into v_temp; if sql%notfound then dbms_output.put_line('Update Failure: ' || sql%rowcount); else dbms_output.put_line('Update Success: ' || sql%rowcount || ' ' || v_temp.tname); if sql%isopen then dbms_output.put_line('The cursor is open!'); else dbms_output.put_line('The cursor is close!'); end if; end if;end;select * from temp;----implicit cursor:bulk collectdelete from temp;insert into temp values ('1','meilin');insert into temp values ('2','bing');insert into temp values ('3','qing');declaretype temp_type is table of temp%rowtype index by binary_integer;v_temp temp_type;begin select * bulk collect into v_temp from temp; for i in 1.. v_temp.count loop dbms_output.put_line('tname:' || v_temp(i).tname); end loop;end;----forall:reduce transfer data times between PL/SQL ?engine and SQL ?engine,upgrade db performance;drop table param;create table param( pname varchar2(20))declaretype temp_tname_type is table of temp.tname%type index by binary_integer;v_tname temp_tname_type;begin select custname bulk collect into v_tname from customer where custid = '96'; forall i in 1..v_tname.count insert into param values (v_tname(i)); dbms_output.put_line(sql%bulk_rowcount(1) || '--' || v_tname(1)); commit; ----rollback;end;select * from param;----transactiondelete from param;begin ----transaction start insert into param values ('Java'); savepoint spj; insert into param values ('Python'); savepoint spp; insert into param values ('Dotnet'); savepoint spd; rollback to savepoint spj; commit; exception when others then rollback;end;select * from param;----lockupdate temp set tname = 'lock' where tid = '1';----transaction isolation(to be continued)?
Oracle系列SQL及数据库下载：http://download.csdn.net/source/3046868
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