[CALCITE-5469] Implement BigQuery DATETIME_ADD/DATETIME_DIFF

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.34.0
• Labels: pull-request-available
• Assignee: Tanner Clary
• Reporter: Tanner Clary
• Created: 12/Jan/23 15:19
• Updated: 16/Mar/23 08:46
• Resolved: 26/Feb/23 02:55

Description

Add support for BigQuery's DATETIME_ADD/DATETIME_DIFF functions.

DATETIME_ADD(datetime, interval) can accept a timestamp (or a datetime, which is an alias for timestamp) for its first argument and an interval for its second. The output is the datetime that occurs interval after the provided datetime.

DATETIME_DIFF(datetime, datetime2, timeUnit) returns the whole number of timeUnit between datetime and datetime2, with the result being negative if datetime occurs before datetime2

Examples:
DATETIME_ADD(TIMESTAMP '2008-12-25 15:30:00', INTERVAL 5 MINUTE) would return: '2008-12-25 15:35:00'.

DATETIME_DIFF(DATETIME '2008-12-25 15:30:00', DATETIME '2008-12-26 15:30:00', DAY) would return: -1.

Issue Links

• relates to: CALCITE-5575 Incorrect priority of builtinFunctionCallMethods in Parser.jj
• relates to: DRILL-8410 Upgrade to Calcite 1.34
• links to: GitHub Pull Request #3024
• links to: GitHub Pull Request #3079