Transcript The New Data Pump

The New Data Pump
Caleb Small
[email protected]
Next generation Import / Export
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New features
Better performance
Improved security
Versatile interfaces
Old Import / Export
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Still exists
Installed and enabled by default
Supports features through version 9i
No new releases
Required to import pre-10g dump files
Dump files & scripts are NOT compatible
New Features
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Data Sampling & filtering
Object filtering
Estimate file size, max file size, multiple files
Remap datafile, schema, tablespace
Network mode
Point-in-time export
Version conversion
Column data encryption
Better Performance
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Complete re-write
Parallel processing
Parallel data streams to multiple files
Runs within the instance
Uses direct path whenever possible
Restartable
Tunable (auto tuning)
Progress monitoring
Improved Security
• Server based only – no client side exports!
• Based on directory objects within database
• Always runs as “oracle” process on behalf
of invoking database user.
Versatile Interfaces
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Command line
Parameter file
Interactive mode
DBMS_DATAPUMP package
DB console (Enterprise manager)
External table
Scheduled job
Datapump Architecture
• Master process
• Manages and controls the operation
• Worker process(es)
• Responsible for data movement
• One for each degree of parallelism
• Master table
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Created in invokers schema at job start
Maintained during job execution
Dropped after successful completion
Used to resume a paused/failed job
• Control & status queues
Types of Exports
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Table
Schema
Tablespace
Database
Transportable Tablespace (metadata)
INCLUDE / EXCLUDE object filters
QUERY and SAMPLE data filters
CONTENTS = data | metadata | both
Directory Objects
• Created as a database object
• Requires CREATE_ANY_DIRECTORY privilege
• Permissions (read, write) granted on the object
to specific user(s)
• Not validated – existence, syntax, OS privilege
• Accessed as user “oracle” at the OS level
• Default DATA_PUMP_DIR maps to …
Data Access
• Direct Path
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Chosen automatically whenever possible
Reads/writes data blocks directly
No undo, redo can be turned off
See Utilities Guide for exceptions (eg. active
triggers, clustered tables, BFILE column, etc)
• External Table
• Equivalent to old “conventional path”
• Normal SQL and commit processing, slower
• NOT the same as the external table driver for SQL
Monitoring Data Pump
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STATUS parameter
Detach / re-attach jobs
Stop / start / kill jobs
STATUS command (interactive mode)
Data dictionary views
• DBA_DATAPUMP_JOBS
• DBA_DATAPUMP_SESSIONS
• V$SESSION_LONGOPS
• Log File
Interactive Mode
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NOT the same as old imp/exp!
Default starts schema mode export
Use command line arguments or par file
“logging” vs “interactive command” mode
Default logging mode logs to terminal
Ctl-C to enter interactive command mode
Job will continue to run even if client disconnects!
expdp scott/tiger@fred parfile=myjob.par
Interactive Mode Commands
STATUS
CONTINUE_CLIENT
EXIT_CLIENT
STOP_JOB
START_JOB
KILL_JOB
PARALLEL
ADD_FILE
HELP
Status of current job
Resume “logging” mode
Exit client, leave job running
Stop current job, do not delete
Re-start current job
Delete current job
Add/remove worker processes
Add dump file during export
Get help
Obsolete Parameters
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Export
BUFFER
COMPRESS
CONSISTENT
DIRECT
RECORD_LENGTH
RESUMABLE
STATISTICS
USERID
VOLSIZE
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Import
BUFFER
CHARSET
COMMIT
COMPILE
FILESIZE
RECORD_LENGTH
RESUMABLE
STATISTICS
Others have changed, see the Utilities Guide!
Data Pump API
• Grant execute on DBMS_DATAPUMP and
optionally DBMS_METADATA
• Exec DBMS_DATAPUMP.OPEN
• Define parameters (job type, dump file, etc)
• Exec DBMS_DATAPUMP.START_JOB
• Optionally monitor, detach, re-attach, stop,
start or kill the job
• Can be scheduled as a recurring job
External Table (SQL)
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Created as a database object (TABLE)
Organization EXTERNAL
Uses ORACLE_DATAPUMP access driver
Can load and unload data
Dumpfile contains row data only
Metadata stored in data dictionary
Not compatible with regular dump file
Network Mode
• Works across database link
• Import reads tables from remote DB and
writes directly to tables in local DB
– No dump file created
– Directory object still required for logging
• Export reads tables from remote DB and
writes to dump file on local server
SQL File
• Import can generate an SQL file instead of
actually performing the import
• Contains DDL that would have been
executed based on job parameters
• Passwords excluded
• No change to target DB
Required Reading
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Oracle Database New Features Guide
Oracle Database Utilities
PL/SQL Packages and Types Reference
Oracle Data Pump FAQ on OTN
Demonstration
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Directory object basics
Basic Data Pump unload and load
Query / Sample data filtering
Re-attaching and monitoring a big job
The PL/SQL API
SQL File import
External Table access driver
www.caleb.com/dba
[email protected]
Tuning Data Pump
• PARALLEL is the only DP specific parameter
• Set to 2 times number of CPUs
• Will cause increased resource consumption
• Memory, CPU, I/O bandwidth
• Do not overload these resources!
• Individual worker processes can use parallel query
• Use multiple dump files to maximize parallelism
• Separate files on separate physical devices/channels
• Use wildcard in filename eg: dumpfile%u.dmp
• Separate device/channel from source tablespace(s)
Tuning Data Pump
Instance parameters that may affect performance:
• DISK_ASYNCH_IO=TRUE
• DB_BLOCK_CHECKING=FALSE
• DB_BLOCK_CHECKSUM=FALSE
• PROCESSES
• SESSIONS
• PARALLEL_MAX_SERVERS
• SHARED_POOL_SIZE
• UNDO_TABLESPACE