You have several options when loading and deleting large volumes
of data, as described in the following sections.
Bulk Inserts: Using the SQL*Loader Direct Path Option
When used in the Conventional Path mode, SQL*Loader reads records from a file, generates
insert commands, and passes them to the Oracle kernel. Oracle then finds places for those rows
in free blocks in the table and updates any associated indexes.
In Direct Path mode, SQL*Loader creates formatted data blocks and writes directly to the
datafiles. This requires occasional checks with the database to get new locations for data blocks,
but no other I/O with the database kernel is required. The result is a data load process that is
dramatically faster than Conventional Path mode.
If the table is indexed, the indexes will be placed in DIRECT PATH state during the load. After
the load is complete, the new keys (index column values) will be sorted and merged with the
existing keys in the index. To maintain the temporary set of keys, the load will create a temporary
index segment that is at least as large as the largest index on the table. The space requirements
for this can be minimized by presorting the data and using the SORTED INDEXES clause in the
SQL*Loader control file.
To minimize the amount of dynamic space allocation necessary during the load, the data
segment that you are loading into should already be created, with all the space it will need
already allocated.
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