Exporting/Importing Large Data
Posted by Rajkiran Ghanta on November 21, 2007
When exporting Large data, you can specify multiple files in the export command. This can be used from Oracle 8i version.
$> exp testuser1/testuser1 files=/oraexport/data/tab1.dmp, /oraexport/data/tab2.dmp filesize=1024m log=large_exp.log
Please note that the export files need to be specified in the same order, when you import the data.
Or else, you can write the export data to a pipe and compress the data before writing to a file.
for export :
$PIPE=/tmp/exp_ora9i.dmp
$MAXSIZE=1024m
$ExportFile=employees.dmp
$ExportLog=exp_employees.log
$mknod $PIPE p
$ORACLE_USER=testuser1/testuser1
$ParamString=”compress=n feedback=10000 tables=employees log=$ExportLog statistics=none”
$( gzip < $PIPE ) split -b $MAXSIZE – $ExportFile. & $exp $ORACLE_USER buffer=2000000 constraints=n triggers=n grants=n indexes=n file=$PIPE $ParamString
To import the data exported as above, you can uncompress the data to a pipe and use the same pipe to import.
$PIPE=/tmp/imp_ora9i.dmp
$mknod $PIPE p
$ORACLE_USER=testuser2/testuser2
$cat `echo employees.* sort` gunzip > $PIPE &
$imp $ORACLE_USER file=$PIPE ignore=y
