How to export selective rows
You can export a selective rows of table with a new introduced QUERY option of export.You can use QUERY option on command line as well as in parameter file. Preferable way is to use parameter file.
Method 1 :- Command line
ON WINDOWS PLATFORM
Task:- Export only rows of table emp where comm. > 20
Construct the export command as follows :-
E:\ora816\BIN>exp scott/tiger file=c:\temp\emp.dmp log=c:\temp\emp.log tables=emp query="""where comm > 20"""
NOTE: You have to put three double quotes before and after the statement ="""where comm > 20""" . There should be NO spaces surrounding the double quotes and NO spaces between the double quotes either.
ON UNIX
Task:- Export only rows of table emp where comm. > 20 and ename = SAMEER
Construct the exp command as follows :-
$exp query=\" where comm \>20 and ename \= \'SAMEER\' \" tables=emp userid=scott/tiger
Note :- You have to put \ before each operator , surround non-numeric condition and at beginning and end of the query statement.
METHOD 2: USE OF PARAMETER FILE
This method is same on unix and nt.
Construnct the query clause in parfile as follows
Exppar.dat
file=expemp.dm
query="where enum > 12345"
tables=(emp)
log=emp.txt
userid=scott/tiger
You can also use subquery in the query clause as
Exppar.dat
file=expemp.dmp
query="where deptno in (Select deptno from dept where deptno in ('10','20'))"
tables=(emp)
log=emp.txt
userid=scott/tiger
Here the export is only for the employees who are in dept no 10 and 20 from dept table
Comments
Post a Comment