The following example shows how an external table can be used to query theĬREATE OR REPLACE DIRECTORY bdump AS '/u01/app/oracle/admin/SID/bdump/' Remember, every query of the external table causes the file(s) to be readĪgain, so try to make as few passes over the external table as possible. By default, the badįile is created in the same directory as the load files, but this can be The load files, but this can be changed using the LOGFILE parameter.įield Definitions for table COUNTRIES_EXTĭata in file has same endianness as the platformĪny rows that fail to load are written to a bad file. Once the table is functioning correctly we can create views against it.ĬREATE OR REPLACE VIEW english_speaking_countries ASīy default, a log of load operations is created in the same directory as KUP-04040: file Countries1.txt in EXT_TAB_DATA not found ORA-29913: error in executing ODCIEXTTABLEOPEN callout If the load files have not been saved in the appropriate directory the Once the external table created, it can be queried like a regular table. LOCATION ('Countries1.txt','Countries2.txt') This defines the metadata for the table describing how Two files which should be saved to a filesystem available to the OracleĬreate a directory object pointing to the location of the files.ĬREATE OR REPLACE DIRECTORY ext_tab_data AS '/data' Ĭreate the external table using the CREATE TABLE.ORGANIZATIONĮXTERNALsyntax. They should not be usedĬontaining the data to be queried. Need to be staged and can be queried in parallel. TheyĪre useful in the ETL process of data warehouses since the data doesn't Views and synonyms can be created against external tables. Performed on external tables but they can be used for query, join and sort The ORACLE_LOADER driver can be used to access anyĭata stored in any format that can be loaded by SQL*Loader. External Tables: Querying Data From Flat Files in OracleĮxternal tables allow Oracle to query data that is stored outside theĭatabase in flat files.
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