feat(query): add date_diff function

[chagelo]

I hereby agree to the terms of the CLA available at: https://docs.databend.com/dev/policies/cla/

Summary

related to #16534

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

---

This change is 

[TCeason]

select date_diff(year, to_timestamp('2020-02-29 23:59:59.165575'), to_timestamp('2019-02-28 23:59:59.423179'))

expect -1

[TCeason]

I test in snowflake , select datediff(quarter, to_timestamp('2020-02-29 23:59:59.165575'), to_timestamp('2019-02-28 23:59:59.423179')) expect -4

[TCeason]

select datediff(year, to_timestamp('2023-11-12 09:38:18.165575'), to_timestamp('2025-03-27 21:01:35.423179')) expect 2.

[TCeason]

consider test select DATE_DIFF(YEAR, TO_TIMESTAMP('2023-12-31 09:38:18.165575'), TO_TIMESTAMP('2024-01-01 21:01:35.423179')) the result should be 1.

[TCeason]

Also need to add some tests where the sign is negative

[chagelo]

Sorry, I got you. But, what's the result of select date_diff(year, to_date('2023-12-31'), to_date('2024-01-01'))?

[TCeason]

Sorry, I got you. But, what's the result of select date_diff(year, to_date('2023-12-31'), to_date('2024-01-01'))?

Oh, I just mean add a logic test case:

query T
SELECT DATE_DIFF(YEAR, to_date('2023-12-31'), to_date('2024-01-01'))
----
1

[chagelo]

So what should I do is to fix it to be compatible with Snowflake and add more tests?

[TCeason]

So what should I do is to fix it to be compatible with Snowflake and add more tests?

Date diff about year just need to evaluate year sub. E.g.

2023-12-31 2024-01-01 just need to calc year sub.

[chagelo]

Ok, thank you. TCeason ***@***.***> 于2024年10月8日周二 14:33写道：

…

So what should I do is to fix it to be compatible with Snowflake and add more tests? Date diff about year just need to evaluate year sub. E.g. 2023-12-31 2024-01-01 just need to calc year sub. — Reply to this email directly, view it on GitHub <#16560 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AL4OCSKJ7XXJNNZXDXK7I53Z2N4E7AVCNFSM6AAAAABPGYZISGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGOJYHE3DMNBQGI> . You are receiving this because you authored the thread.Message ID: ***@***.***>