TO_TIMESTAMP

See below for the formatting function that converts from a formatted string to TIMESTAMPTZ.

Alias: FROM_UNIXTIME - only accepts one parameter of type DOUBLE PRECISION

Conversion function

Converts the number of seconds since the Unix epoch (1970-01-01 00:00:00 UTC) to a TIMESTAMPTZ value.

Syntax

TO_TIMESTAMP(<seconds>)

Parameters

Parameter	Description
`<seconds>`	A value expression of type `DOUBLE PRECISION` representing the number of seconds before or after the Unix epoch. If present, the fractional part is interpreted as subseconds.

Return Type

TIMESTAMPTZ

Remarks

TO_TIMESTAMP(<seconds>) is the inverse function of EXTRACT(EPOCH FROM TIMESTAMPTZ).

Example

SET time_zone = 'Europe/Berlin';
SELECT TO_TIMESTAMP(42.123456::DOUBLE PRECISION);  --> 1970-01-01 01:00:42.123456+01

Formatting function

Converts a string to TIMESTAMPTZ type (i.e., timestamp with time zone) using format.

Syntax

TO_TIMESTAMP(<expression> [,'<format>'])

Parameters

Parameter	Description	Supported input types
`<expression>`	The text to convert to a timestamp with time zone. If no optional `<format>` argument is given that can be used to parse the `<expression>`, the following format is required: any supported date format directly followed by `( \\|T)[H]H:[m]m:[S]S[.F]`. (For supported date formats see TO_DATE	`TEXT`
`<format>`	Optional. A string literal that specifies the format of the `<expression>` to convert.	`TEXT` (see below)

Accepted <format> patterns include the following specifications:

Format option	Description	Example
`YYYY`	Year (4 or more digits)	`TO_TIMESTAMP('2023', 'YYYY'); --> '2023-01-01 00:00:00+00'`
`YYY`	Last 3 digits of year	`TO_TIMESTAMP('2023', 'YYY'); --> '2023-01-01 00:00:00+00'`
`YY`	Last 2 digits of year	`TO_TIMESTAMP('2023', 'YY'); --> '2023-01-01 00:00:00+00'`
`Y`	Last digit of year	`TO_TIMESTAMP('2023', 'Y'); --> '2023-01-01 00:00:00+00'`
`MONTH`	Full month name (case insensitive)	`TO_TIMESTAMP('august', 'MONTH'); --> '0001-08-01 00:00:00+00'`
`MON`	abbreviated month name (3 chars, case insensitive)	`TO_TIMESTAMP('dec', 'MON'); --> '0001-12-01 00:00:00+00'`
`MM`	Month number (01–12)	`TO_TIMESTAMP('7', 'MM'); --> '0001-07-01 00:00:00+00'`
`DD`	Day of month (01–31)	`TO_TIMESTAMP('15', 'DD'); --> '0001-01-15 00:00:00+00'`
`HH` or `HH12`	Hour of day (01–12)	`TO_TIMESTAMP('8', 'hh'); --> '0001-01-01 08:00:00+00'`
`HH24`	Hour of day (00–23)	`TO_TIMESTAMP('18', 'hh24'); --> '0001-01-01 18:00:00+00'`
`MI`	Minute (00–59)	`TO_TIMESTAMP('35', 'hh'); --> '0001-01-01 00:35:00+00'`
`SS`	Second (00–59)	`TO_TIMESTAMP('52', 'hh'); --> '0001-01-01 00:00:52+00'`
`MS`	Millisecond (000–999)	`TO_TIMESTAMP('89', 'ms'); --> '0001-01-01 08:00:00.89+00'`
`US`	Microsecond (000000–999999)	`TO_TIMESTAMP('04852', 'hh'); --> '0001-01-01 08:00:00.04852+00'`
`AM` or `PM`	meridiem indicator (without periods)	`TO_TIMESTAMP('5 am', 'hh PM'); --> '0001-01-01 05:00:00+00+00'`
`A.M.` or `P.M.`	meridiem indicator (with periods)	`TO_TIMESTAMP('5 p.m.', 'hh A.M.'); --> '0001-01-01 17:00:00+00'`
`TZH`	Time zone hours	`TO_TIMESTAMP('12 -2', 'hh24 TZH'); --> '0001-01-01 14:00:00+00+00'`
`TZM`	Time zone minutes	`TO_TIMESTAMP('12 45', 'hh24 TZM'); --> '0001-01-01 11:15:00+00`

Usage notes for formatting

Case letters in the input <expression> are ignored
A separator (non-digit and non-letter) in the <format> string will match exactly one separator or is skipped
Any non-separator in the <format> that is not part of a format option will match exactly one other character.
Any character in quotes " will match exactly one other character.
If the year format specification is 'YYY', 'YY', or 'Y' and the supplied year is less than four digits, the year will be adjusted to be nearest to the year 2020, (e.g., 80 becomes 1980).
Milliseconds and microseconds are interpreted as subseconds in the form ss.xxx[xxx]. This means that TO_TIMESTAMP('30.7', 'SS.MS') is not 7 milliseconds, but 700, because it will be treated as 30 + 0.7 seconds. To achieve 7 milliseconds, one ust write 30.007 instead.
Modifiers (e.g., 'FM') are not supported.

Some additional format patterns are reserved but currently not implemented: FF1, FF2, FF3, FF4, FF5, FF6, SSSS, SSSSS, IYYY, IYY, IY, I, BC, AD, B_DOT_C_DOT, A_DOT_D_DOT, DAY, DY, DDD, IDDD, D, ID, W, WW, IW, CC, J, Q. Using them in the format string raises an error.

Examples

The example below shows our separators and non-separators can cause skips. The separator ' ' (space) in the <format> matches the other separator '/' in the <expression>. The non-separator 'x' will match any other character, in this case the 'a'. Lastly, the two separators '++' will match up to two other separators, here the first 'x' matches '.' while the second 'x' will simply be ignored as no other separators follow.

SELECT
TO_TIMESTAMP(
'2023/aJUN.23',
'YYYY xMON++DD'
) as ts;

ts (TIMESTAMPTZ)
‘2023-06-23 00:00:00+00’

The example below shows how the year is adjusted to be nearest to 2020 because YYY was used to match a less than four digit number. To receive the exact year '180' use YYYY instead. Furthermore, as the three separators are quotes "..." they will match any character (separator or non-separator) which in this case is 'ar '.

SELECT
TO_TIMESTAMP(
'Year 180: August 4th',
'xx"..."yyy: month DDxx'
) as ts;

ts (TIMESTAMPTZ)
‘2180-08-04 00:00:00+00’

SELECT
TO_TIMESTAMP(
'Date: August 2nd, 2023 at 3pm +2',
'Xxxx: month DDxx, YYYY at HH12am TZH'
) as ts;

ts (TIMESTAMPTZ)
‘2023-08-02 13:00:00+00’

SELECT
TO_TIMESTAMP(
'h:19 m:34 s:29 ms:035 us:000123',
'X:hh24 X:mi X:ss XX:ms XX:us'
) as ts;

ts (TIMESTAMPTZ)
‘0001-01-01 19:34:29.035123+00’

SELECT
FROM_UNIXTIME(
1728053781.761451
) as ts;

ts (TIMESTAMPTZ)
‘2024-10-04 14:56:21.761451+00’

Due to rounding it can happen that the conversion from an extracted epoch back to a timestamp does not generate the original timestamp.

WITH data as (
select '1597-12-03 13:49:30.511757+00'::timestamptz as ts
)
SELECT
ts as original_ts,
FROM_UNIXTIME(
extract(epoch from ts)
) as converted_ts
FROM data

original_ts (TIMESTAMPTZ)	converted_ts (TIMESTAMPTZ)
‘1597-12-03 13:49:30.511757+00’	‘1597-12-03 13:49:30.511756+00’