Importing and exporting data

Before actually diving into backup and recovery, it is useful to take a general look at importing and exporting data from, and into, PostgreSQL. Understanding imports and exports is quite essential to get the overall idea of backups on a technical level.

Using the COPY command

When talking about imports and exports, there is really no way to do it without discussing the COPY command. The COPY command is the backbone of all the operations—it makes importing and exporting to the database very easy and offers a great deal of flexibility. Here is the syntax of this wonderful command:

test=# \h COPY
Command:     COPY
Description: copy data between a file and a table
Syntax:
COPY table_name [ ( column_name [, ...] ) ]
    FROM { 'filename' | PROGRAM 'command' | STDIN }
    [ [ WITH ] ( option [, ...] ) ]
COPY { table_name [ ( column_name [, ...] ) ] | ( query ) }
    TO { 'filename' | PROGRAM 'command' | STDOUT }
    [...