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Short answer

In most cases, a combination of date, time, timestamp without time zone, and timestamp with time zone should provide a complete range of date/time functionality required by any application. (S1) Get the current time with current_timestamp (start of the transaction) or clock_timestamp() (changes during a statement). [S1][S2]

SELECT current_timestamp, statement_timestamp(), clock_timestamp();
SELECT now() AT TIME ZONE 'UTC';

Key points

• transaction_timestamp() and statement_timestamp() also return timestamptz. [S2]
• The output format of the date/time types can be set to one of the four styles ISO 8601, SQL (Ingres), traditional POSTGRES (Unix date format), or German. (S1)

Claims

• id: C1 claim: timestamp without time zone stores date and time with no zone. source: S1 evidence: "both date and time (no time zone)"
• id: C2 claim: Output can be ISO 8601 with time zone as UTC offset. source: S1 evidence: "ISO 8601, with time zone as UTC offset"
• id: C3 claim: current_timestamp returns timestamp with time zone. source: S2 evidence: "current_timestamp → timestamp with time zone"
• id: C4 claim: clock_timestamp returns timestamp with time zone. source: S2 evidence: "clock_timestamp ( ) → timestamp with time zone"

Sources

• [S1] PostgreSQL: Documentation: 18: 8.5. Date/Time Types. PostgreSQL Global Development Group. https://www.postgresql.org/docs/current/datatype-datetime.html . License: PostgreSQL License. Accessed 2026-11-04.
• [S2] PostgreSQL: Documentation: 18: 9.9. Date/Time Functions and Operators. PostgreSQL Global Development Group. https://www.postgresql.org/docs/current/functions-datetime.html . License: PostgreSQL License. Accessed 2026-11-04.

License: this note is CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Summary by iinventedlight (AI-assisted).

@misc{iil_note_yn7mpned,
  author = {{iinventedlight}},
  title = {{PostgreSQL date/time types and current time functions}},
  howpublished = {iinventedlight Library},
  year = {2026},
  date = {2026-11-04},
  url = {https://iinventedlight.com/library/notes/postgres-date-time-types/},
  note = {Permanent ID iil:note:yn7mpned. License: CC-BY-4.0.},
}

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