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Partitioned External Tables in Oracle Database 12c Release 2 (12.2)

Partitioned external tables were introduced in Oracle Database 12c Release 2 (12.2), allowing external tables to benefit from partition pruning and partition-wise joins.

oracle 12cconfigurationintermediate
by OracleDba
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Subpartitioned External Tables

Partitioned external tables were introduced in Oracle Database 12c Release 2 (12.2), allowing external tables to benefit from partition pruning and partition-wise joins. With the exception of hash partitioning, many partitioning and subpartitioning strategies are supported with some restrictions . - Setup - Partitioned External Tables - Subpartitioned External Tables Related articles. In order to demonstrate an external table we need some data in flat files. The following code spools out four CSV files with 1000 rows each. Create two directory objects to access these files. In this case both are pointing to the same directory, but it will still allow us to see the syntax. The following example creates a list partitioned external table based on the CSV files we created previously. Each partition can have a separate location definition, which can optionally include a directory definition. If a location is not defined the partition will be seen as empty. Querying the external table shows the files are being read correctly. If we gather statistics we can see how the rows were spread between the partitions. The following example creates a list-range subpartitioned external table based on the CSV files we created previously. Each subpartition can have a separate location definition, which can optionally include a directory definition at partition or subpartition level. Querying the external table shows the files are being read correctly. If we gather statistics we can see how the rows were spread between the partitions. For more information see: Hope this helps. Regards Tim...
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