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10 Million records manipulation in Oracle DB

Say you are given a task to manipulate a set of 10 million records from a couple of tables.
What would you do? Sit and think???!!!!

See if the following helps you..

Replicate the tables data into temporary tables
Create indexes on the columns you want to manipulate the data
Write your query..

Dont ask me what language you are talking!!!!
Look at the examples

Select count(1) from hugeTable1;--7999900 records
Select count(1) from hugeTable2; --9893990

Create table tmp1
as
Select *
from hugeTable1
where 1=2;

insert /*+append*/ into tmp1
select * from hugeTable1;

Create table tmp2
as
Select *
from hugeTable2
Where 1=2;

insert /*+append*/ into tmp2
select * from hugeTable2;

create index indTmp1 on tmp1(column1,column2);
create index indTmp2 on tmp2(column1,column2);

Select *
from tmp1,tmp2
where tmp1.column1=tmp2.column1 and
          tmp1.column2=tmp2.column2;
   

Should you face any issues, please write to me ( susilaarya@gmail.com )

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