Thread

1. BUG #19002: `pg_isready` unexpectedly succeeds on incorrect `--dbname` and/or `--username`

   PG Bug reporting form <noreply@postgresql.org> — 2025-07-29T19:11:03Z

   The following bug has been logged on the website:
   
   Bug reference:      19002
   Logged by:          Samuel Marks
   Email address:      samuelmarks@gmail.com
   PostgreSQL version: 17.5
   Operating system:   macOS
   Description:        
   
   ```
   /  > pg_isready -U fff
   /tmp:5432 - accepting connections
   /  > pg_isready -U fff -d555
   /tmp:5432 - accepting connections
   ```
   
   (`fff` is not a user and `555` is not a db on my installation)
   
   

2. Re: BUG #19002: `pg_isready` unexpectedly succeeds on incorrect `--dbname` and/or `--username`

   Jacob Champion <jacob.champion@enterprisedb.com> — 2025-07-29T19:54:43Z

   On Tue, Jul 29, 2025 at 12:45 PM PG Bug reporting form
   <noreply@postgresql.org> wrote:
   > /  > pg_isready -U fff
   > /tmp:5432 - accepting connections
   > /  > pg_isready -U fff -d555
   > /tmp:5432 - accepting connections
   > ```
   >
   > (`fff` is not a user and `555` is not a db on my installation)
   
   Hi Samuel, this behavior is explained in the docs [1]:
   
   > It is not necessary to supply correct user name, password, or database name values to obtain the server status; however, if incorrect values are provided, the server will log a failed connection attempt.
   
   So it's essentially just a courtesy to whoever's watching your logs.
   
   --Jacob
   
   [1] https://www.postgresql.org/docs/current/app-pg-isready.html#APP-PG-ISREADY-NOTES
   
   
   
   

3. Re: BUG #19002: `pg_isready` unexpectedly succeeds on incorrect `--dbname` and/or `--username`

   Samuel Marks <samuelmarks@gmail.com> — 2025-07-30T03:01:16Z

   Hmm I suppose that works, but really I was using it as a "can i connect"
   check. Similar to https://github.com/eficode/wait-for or
   https://github.com/wait4x/wait4x
   
   It seems weird—unexpected to user—to accept dbname or user and not have a
   non-zero exit code or something in stderr indicating failure…
   
   Samuel Marks
   Charity <https://sydneyscientific.org> | consultancy <https://offscale.io>
   | open-source <https://github.com/offscale> | LinkedIn
   <https://linkedin.com/in/samuelmarks>
   
   
   On Tue, Jul 29, 2025 at 2:54 PM Jacob Champion <
   jacob.champion@enterprisedb.com> wrote:
   
   > On Tue, Jul 29, 2025 at 12:45 PM PG Bug reporting form
   > <noreply@postgresql.org> wrote:
   > > /  > pg_isready -U fff
   > > /tmp:5432 - accepting connections
   > > /  > pg_isready -U fff -d555
   > > /tmp:5432 - accepting connections
   > > ```
   > >
   > > (`fff` is not a user and `555` is not a db on my installation)
   >
   > Hi Samuel, this behavior is explained in the docs [1]:
   >
   > > It is not necessary to supply correct user name, password, or database
   > name values to obtain the server status; however, if incorrect values are
   > provided, the server will log a failed connection attempt.
   >
   > So it's essentially just a courtesy to whoever's watching your logs.
   >
   > --Jacob
   >
   > [1]
   > https://www.postgresql.org/docs/current/app-pg-isready.html#APP-PG-ISREADY-NOTES
   >
   

4. Re: BUG #19002: `pg_isready` unexpectedly succeeds on incorrect `--dbname` and/or `--username`

   Tom Lane <tgl@sss.pgh.pa.us> — 2025-07-30T03:27:35Z

   Samuel Marks <samuelmarks@gmail.com> writes:
   > Hmm I suppose that works, but really I was using it as a "can i connect"
   > check.
   
   That's explicitly not its job.  Why don't you just try to connect?
   Or if you want a command-line tool, consider
   
   	psql ...connection options... -c 'select 1'
   
   			regards, tom lane