Oracle Database 11 g - Online Public Access Catalog

CHAPTER 7■ ■ ■Data PumpDBAs and developers have been using the Export and Import utilities since the early releasesof Oracle (versions 6/7) to make logical data backups for development, quality assurance, andeven production environments. Oracle Database 10g introduced a new tool called Data Pumpthat will eventually replace the Export and Import utilities. The objective of the Data Pumputility is to take advantage of modern database features and provide scalability to ever-growingdatabase workloads and sizes. Since Oracle 9i Database, Oracle has no longer made improvementsto the exp or imp utilities.Data Pump provides significant performance improvements over the conventional Exportand Import utilities, especially in the world of large objects and VLDB databases. Data Pumpclaims to be up to two times faster than conventional exports. Oracle Database 11g makessignificant enhancements to the Data Pump tool, adding new features such as data encryption,compression, data remapping capabilities, and file reusability. Data Pump allows faster dataextraction and now even provides security compliance for data at rest.■Note Oracle’s direction is to eventually deprecate the traditional Export utility. Obviously, the deprecationtimeline for the Import utility will be significantly prolonged, because a lot of customers will have in-houseexport dump files from previous releases of Oracle.API EnhancementsData Pump uses the following two Oracle PL/SQL packages:• DBMS_DATAPUMP (also referred to as the Data Pump API)• DBMS_DATAPUMP (also referred to as the Metadata API)The Data Pump utilities (expdp and impdp) simply make calls to the DBMS_DATAPUMP API toperform data extractions or imports. Oracle Database 11g provides a new API that will provideadditional security for companies that need to remap sensitive data for data at rest or transformdata during import operations. The data_remap procedure has been introduced in the DBMS_DATAPUMP package to allow data transformation of pertinent data for Data Pump jobs of data inuser tables. The datatype, structure, and format are still preserved during this operation. Thisfeature to transform data during the export is particularly useful while refreshing the production313