recovery_target_time format explanation should be clarified when using UTC zone
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/18/index.html
Description:
We've been hitting a bug with PITR when specifying a recovery_target_time
with an ISO 8601 format and UTC zone indicated with a trailing `Z`.
We get an error like this
```
"msg":"waiting for server to start....2025-10-28 16:40:20.324 UTC [38]
LOG: invalid value for parameter \"recovery_target_time\": \"2025-10-28
16:34:15.000000Z\"",
```
The documentation states
The value of this parameter is a time stamp in the same format accepted by
the timestamp with time zone data type, except that you cannot use a time
zone abbreviation
[-snip-]
Preferred style is to use a numeric offset from UTC, or you can write a
full time zone name, e.g., Europe/Helsinki not EEST.
That `Z`, if it's an abbreviation, would be an abbreviation for Zulu, I
presume? I tried to use `Zulu` and not just `z` but still had the same
`invalid value` error.
For timestamps in UTC zone, I think the only supported format would be
numeric offset, right? With `+00` instead of `Z`.
I think that the documentation should clarify this explicitly.
Unless there is a full name for the UTC zone which I'm unaware of...
Thanks
Actually, I had not realized there was a “Submit Correction” link on each documentation page.
Sorry, hope I haven’t made this confusing.
The documentation page that requires clarification is
https://www.postgresql.org/docs/current/runtime-config-wal.html#RUNTIME-CONFIG-WAL-RECOVERY-TARGET
19.5. Write Ahead Log
postgresql.org
Show quoted text
On 29 Oct 2025, at 14:58, PG Doc comments form <noreply@postgresql.org> wrote:
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/18/index.html
Description:We've been hitting a bug with PITR when specifying a recovery_target_time
with an ISO 8601 format and UTC zone indicated with a trailing `Z`.We get an error like this
```
"msg":"waiting for server to start....2025-10-28 16:40:20.324 UTC [38]
LOG: invalid value for parameter \"recovery_target_time\": \"2025-10-28
16:34:15.000000Z\"",
```The documentation states
The value of this parameter is a time stamp in the same format accepted by
the timestamp with time zone data type, except that you cannot use a time
zone abbreviation[-snip-]
Preferred style is to use a numeric offset from UTC, or you can write afull time zone name, e.g., Europe/Helsinki not EEST.
That `Z`, if it's an abbreviation, would be an abbreviation for Zulu, I
presume? I tried to use `Zulu` and not just `z` but still had the same
`invalid value` error.For timestamps in UTC zone, I think the only supported format would be
numeric offset, right? With `+00` instead of `Z`.
I think that the documentation should clarify this explicitly.
Unless there is a full name for the UTC zone which I'm unaware of...Thanks