Oracle bulk collect into 的几种用法
bulk collect 和 forall 联合应用写起来显得有些啰嗦,不过为了速度,多写两句又何妨
建立两个临时表
create table T_TEST ( TESTID NUMBER(19) not null, TESTNAME VARCHAR2(512), TESTTYPE VARCHAR2(512), TESTLEVEL VARCHAR2(512), ADDFLAG VARCHAR2(512) ); create table T_TEST2 ( TESTID NUMBER(19) not null, TESTNAME VARCHAR2(512), TESTTYPE VARCHAR2(512), TESTLEVEL VARCHAR2(512), );
存储过程使用示例1:
create or replace procedure FAST_UP_TEST is TYPE TARR is table of T_TEST%ROWTYPE; vvrr TARR; CURSOR curr is select * from T_TEST where ADDFLAG='add'; begin open curr; loop fetch curr bulk collect into vvrr limit 1000; dbms_output.put_line('增加:'||vvrr.count); forall i in 1..vvrr.count update T_TEST2 set TESTTYPE=vvrr(i).TESTTYPE,TESTLEVEL=vvrr(i).TESTLEVEL where TESTNAME=vvrr(i).TESTNAME and TESTID=vvrr(i).TESTID; commit; exit when curr%NOTFOUND; end loop; close curr; end;
换一个方式使用示例(注意游标返回类型变化):
create or replace procedure FAST_DEL_TEST is TYPE TARR is table of T_TEST.TESTID%TYPE; vvrr TARR; CURSOR curr is select TESTID from T_TEST where ADDFLAG='delete'; begin dbms_output.enable(90000); open curr; loop fetch curr bulk collect into vvrr limit 1000; dbms_output.put_line('delete T_TEST '||vvrr.count); forall i in 1..vvrr.count delete T_TEST2 where TESTID=vvrr(i); commit; exit when curr%NOTFOUND; end loop; close curr; end;
多参数返回的另一种用法和动态sql运行办法
create or replace procedure FAST_AD_TEST ( tabtest in VARCHAR2) is TYPE TARR_ID is table of T_TEST.TESTID%TYPE; TYPE TARR_NM is table of T_TEST.TESTNAME%TYPE; TYPE TARR_TP is table of T_TEST.TESTTYPE%TYPE; vvid TARR_ID; vvnm TARR_NM; vvtp TARR_TP; CURSOR curr is select TESTID,TESTNAME,TESTTYPE from T_TEST where ADDFLAG='add'; CURSOR curd is select TESTID from T_TEST where ADDFLAG='delete'; begin execute immediate 'truncate table '||tabtest; -- forall只能写一条sql。。。 open curr; loop fetch curr bulk collect into vvid,vvnm,vvtp limit 1000; forall i in 1..vvid.count insert into T_TEST2(TESTID,TESTNAME,TESTTYPE) values (vvid(i),vvnm(i),vvtp(i)); commit; exit when curr%NOTFOUND; end loop; close curr; -- 动态传入表名和参数 open curd; loop fetch curd bulk collect into vvid limit 1000; forall i in 1..vvid.count execute immediate 'delete '||tabtest||' where TESTID=:tabid' using in vvid(i); commit; exit when curd%NOTFOUND; end loop; close curd; end;
bulk collect 和 forall 的联合应用
基本上压榨出了oracle中增删改的极限速度。
比用游标一条条处理要快太多了。