A technical troubleshooting blog about Oracle with other Databases & Cloud Technologies.

Difference Between exp/imp vs Datapump (expdp/impdp)

2 min read
Below Are the differences b/w exp/imp vs Datapump

1. Datapump operates on a group of files called dump file sets. However, normal export operates on a single file.

2. Datapump access files in the server (using ORACLE directories). Traditional export can access files in client and server both (not using ORACLE directories).

3. Exports (exp/imp) represent database metadata information as DDLs in the dump file, but in datapump, it represents in XML document format.

4. Datapump has parallel execution but in exp/imp single stream execution.

5. Datapump does not support sequential media like tapes, but traditional export supports.

6. Impdp/Expdp use parallel execution rather than a single stream of execution, for improved performance.
 
7. Data Pump will recreate the user, whereas the old imp utility required the DBA to create the user ID before importing.

8. In Data Pump, we can stop and restart the jobs.
 
Why expdp is faster than exp (or) why Data Pump is faster than conventional export/import ??

1. Data Pump is block mode, exp is byte mode.

2. Data Pump will do parallel execution.

3. Data Pump uses direct path API.

4. In Data Pump, where the jobs info will be stored (or) if you restart a job in Data Pump, how it will know from where to resume – Whenever Data Pump export or import is running, Oracle will create a table with the JOB_NAME and will be deleted once the job is done. From this table, Oracle will find out how much job has completed and from where to continue etc.

5. Default export job name will be SYS_EXPORT_XXXX_01, where XXXX can be FULL or SCHEMA or TABLE.

6. Default import job name will be SYS_IMPORT_XXXX_01, where XXXX can be FULL or SCHEMA or TABLE.

7. Datapump gives 15 – 50% performance improvement than exp/imp.

8. Export and import can be taken over the network using database links even without generating the dump file using NETWORK_LINK parameter.

9. CONTENT parameter gives the freedom for what to export with options METADATA ONLY, DATA, BOTH.

Few parameter name changes in datapump and it always makes confusion with parameters in normal exp/imp:

SLNOEXP/IMP ParameterEXPDP/IMPDP Parameter
1ownerschemas
2filedumpfile
3loglogfile/nologfile
4IMP: fromuser, touserIMPDP: remap_schema