Answer Posted / jayaprakash gutti

External table is a complement to SQl* Loader.
External table is more faster compared to SQL loader when
there is thousands of records in source data file.

When we create External table, a link is established between
external table and source data file (which is located in the
file system/Oracle Server).

whenever we query external table like:

select * from external_table;

it fetches data from the file and displayed.
also, external tables are read-only.
you can't perform DML operations.

we can insert the data in the external table to any of the
data base table we want.

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