PolarDB:pldebugger

Prerequisites

Before you begin, ensure that you have:

• pgAdmin 4 v4.19 or later. Download it from pgadmin.org/download.

Connection limits

Each PolarDB for PostgreSQL cluster supports up to three concurrent debugging sessions. Each session uses two connections, so the cluster allows a maximum of six pldebugger connections at a time.

If you need more than three concurrent sessions, go to the Quota Center and click Apply in the Actions column for PolarDB PG pldebugger plug-in use.

If three sessions are already active and you need to start a new one, close one of the existing sessions first.

Create the pldebugger extension

Run the following command as a superuser:

CREATE EXTENSION IF NOT EXISTS pldbgapi;

Debug a function

1. Connect pgAdmin 4 to your PolarDB for PostgreSQL cluster. For details, see .

2. In the object tree, find the function to debug. Right-click it and choose Debugging > Debug.

   

3. The debugger opens in the main panel.

   

   • In the function debugging section on the right, use the toolbar to control execution: step into/over, continue, set breakpoints, and stop.

   • At the bottom of the page, inspect local variables, debugging results, and function stacks during the debugging session.

Monitor connections

To check how many pldebugger connections are currently in use, run:

SELECT * FROM polar_monitor_pldebugger_count();

Sample output:

 current_connection | max_connection
--------------------+----------------
                  6 |              6
(1 row)

In this example, six connections are in use. Because each debugging session requires two connections, this means three sessions are active — the maximum allowed.