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<code class="filename">test_decoding</code> is an example of a logical decoding
output plugin. It doesn't do anything especially useful, but can serve as
a starting point for developing your own output plugin.
</p><p>
<code class="filename">test_decoding</code> receives WAL through the logical decoding
mechanism and decodes it into text representations of the operations
performed.
</p><p>
Typical output from this plugin, used over the SQL logical decoding
interface, might be:
</p><pre class="programlisting">
postgres=# SELECT * FROM pg_logical_slot_get_changes('test_slot', NULL, NULL, 'include-xids', '0');
lsn | xid | data
-----------+-----+--------------------------------------------------
0/16D30F8 | 691 | BEGIN
0/16D32A0 | 691 | table public.data: INSERT: id[int4]:2 data[text]:'arg'
0/16D32A0 | 691 | table public.data: INSERT: id[int4]:3 data[text]:'demo'
0/16D32A0 | 691 | COMMIT
0/16D32D8 | 692 | BEGIN
0/16D3398 | 692 | table public.data: DELETE: id[int4]:2
0/16D3398 | 692 | table public.data: DELETE: id[int4]:3
0/16D3398 | 692 | COMMIT
(8 rows)
</pre><p>
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