Firebird External Tables

Question

I am trying to find a way to quickly load a lot of data into database and one suggested to use Firebird External Tables, I would like know more about this method, I've tried searching online but I'm not getting the useful information about this, I want to know how do they really work? Do the tables have to be exactly the same? and what if you are loading data from more than one database?

Answer 1

Use external tables like this:

CREATE TABLE ext1 EXTERNAL 'c:\myfile.txt'
(
field1 char(20),
field2 smallint
);

To do quick import into regular table, do something like this:

INSERT INTO realtable1 (field1, field2)
SELECT field1, field2 FROM ext1;

Remember to disable triggers and indexes (if possible) before loading, and reactivate them after.

This information is from Firebird FAQ: http://www.firebirdfaq.org/faq209/

Here's more information about using external tables, including information about file format: http://www.delphiman.de/Bin/UsingExternalFilesAsTables.pdf