/pg_savior

A postgres extension to avoid accidental mistakes

Primary LanguageCApache License 2.0Apache-2.0

pg_savior

pg_savior is a PostgreSQL extension designed to prevent accidental data loss due to non-parameterized DELETE queries without a WHERE clause. It hooks into the query execution path.

Warning

The extension is currently under active development. This project is not ready for production yet.

Features

  • Detect DELETE queries without a WHERE clause
  • Detect DELETE queries which use index scan
  • Detects DELETE queries which uses CTE & subqueries
  • Prevent CREATE INDEX without concurrently
  • Prevent DROP DATABASE command

Installation

  1. Clone the repository.
  2. Navigate to the repository directory.
  3. Run make to build the extension.
  4. Run sudo make install to install the extension.

Demo

$ psql -U visi -d postgres psql
(14.9 (Homebrew))
Type "help" for help.

postgres=#
postgres=# create extension pg_savior;
CREATE EXTENSION

postgres=# select * from emp;
id
----
(0 rows)

postgres=# insert into emp values(1);
INSERT 0 1

postgres=# delete from emp;
INFO: pg_savior: DELETE statement detected
INFO: pg_savior: WHERE clause is mandatory for a DELETE statement
DELETE 0

postgres=# select * from emp;
id
----
 1
(1 row)

Usage

After installing the extension, you can enable it in your PostgreSQL database with the following command:

CREATE EXTENSION pg_savior;

Test

The test suite of pg_savior uses pg_yregres. To run a specific test,

pg_yregress tests/D0001.yml
TAP version 14
1..4
# Initializing instances
# Subtest: initialize instance `default`
    1..2
    ok 1 - create extension pg_savior
    ok 2 - create table emp ( id int )
ok 1 - initialize instance `default`
INFO:  pg_savior: ExecutorStart_hook called
INFO:  pg_savior: ExecutorStart called
INFO:  pg_savior: queryDesc->sourceText: select oid, typname from pg_type
# Done initializing instances
ok 2 - D0001: pg_savior: Check if pg_savior is installed
# Subtest: D0001: pg_savior: delete without where clause
    1..6
    ok 1 - insert into emp values (1)
    ok 2 - insert into emp values (2)
    ok 3 - insert into emp values (3)
    ok 4 - select count(*) from emp as count
    ok 5 - delete from emp
    ok 6 - select count(*) from emp as count
ok 3 - D0001: pg_savior: delete without where clause