Wednesday, September 4, 2024

Oracle EXPDP commands




The expdp (Data Pump Export) utility is used to export data and metadata from an Oracle database. It provides several command-line options to customize the export process. Below are some common expdp commands and their explanations:


Basic Syntax:

 


expdp [username/password] DIRECTORY=directory_name DUMPFILE=dumpfile_name LOGFILE=logfile_name [options]


Common Expdp Commands:

    • Export a Full Database:

expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=full_db.dmp LOGFILE=full_db.log

    • FULL=Y: Exports the entire database.
    • Export a Specific Schema:

expdp system/password SCHEMAS=schema_name DIRECTORY=dpump_dir DUMPFILE=schema.dmp LOGFILE=schema.log
    • SCHEMAS=schema_name: Exports a specific schema.
    • Export Specific Tables:

expdp system/password TABLES=table1,table2 DIRECTORY=dpump_dir DUMPFILE=tables.dmp LOGFILE=tables.log
    • TABLES=table1,table2: Exports specific tables.
    • Export a Specific Table with Data and Metadata:

expdp system/password TABLES=table_name DIRECTORY=dpump_dir DUMPFILE=table.dmp LOGFILE=table.log
    • TABLES=table_name: Exports a specific table.
    • Export with Compression:

expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=full_db.dmp LOGFILE=full_db.log COMPRESSION=ALL
    • COMPRESSION=ALL: Compresses all data during export.
    • Export with Data Filtering (e.g., Export Data from a Specific Date):

expdp system/password TABLES=table_name DIRECTORY=dpump_dir DUMPFILE=table.dmp LOGFILE=table.log QUERY=table_name:"WHERE created_date > TO_DATE('2024-01-01', 'YYYY-MM-DD')"
    • QUERY=table_name:"WHERE condition": Filters rows based on a condition.
    • Export Metadata Only:
    • expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=metadata.dmp LOGFILE=metadata.log CONTENT=METADATA_ONLY
    • CONTENT=METADATA_ONLY: Exports only metadata (no data).
    • Export Data Only:

expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=data_only.dmp LOGFILE=data_only.log CONTENT=DATA_ONLY
    • CONTENT=DATA_ONLY: Exports only data (no metadata).
    • Export a Database with a Specific Date Format:

expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=full_db.dmp LOGFILE=full_db.log PARALLEL=4
    • PARALLEL=4: Uses 4 parallel threads for faster export.
  • Export with a Job Name:


expdp system/password FULL=Y DIRECTORY=dpump_dir DUMPFILE=full_db.dmp LOGFILE=full_db.log JOB_NAME=export_full_db
    • JOB_NAME=export_full_db: Assigns a name to the export job.


Additional Parameters:

  • CONTENT: Specifies whether to export metadata only (METADATA_ONLY), data only (DATA_ONLY), or both (ALL).
  • EXCLUDE: Excludes specific objects or object types from the export. Example: EXCLUDE=TABLE:"='table_name'".
  • INCLUDE: Includes specific objects or object types in the export. Example: INCLUDE=TABLE:"IN ('table1', 'table2')".
  • REMAP_SCHEMA: Remaps schema names. Example: REMAP_SCHEMA=old_schema:new_schema.
  • REMAP_TABLESPACE: Remaps tablespace names. Example: REMAP_TABLESPACE=old_tablespace:new_tablespace.


Directory Object:

Before running expdp, ensure that the DIRECTORY object exists in the database and points to a valid filesystem directory where the dump files will be written.

 

 

CREATE OR REPLACE DIRECTORY dpump_dir AS '/path/to/directory';


Example Execution:

To execute an expdp command, open a command prompt or terminal and run the appropriate expdp command based on your requirements. Ensure you have the necessary privileges and that the Oracle environment variables (ORACLE_HOME and PATH) are set correctly.



Conclusion:

The expdp utility offers powerful options for exporting data and metadata from Oracle databases. By using the appropriate parameters and options, you can tailor the export process to meet specific needs and optimize performance.

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