DateTime rounding error
Nobody has claimed this yet.
- Dominant language
- C#
- Stars
- 18.4k
- Forks
- 3.7k
- Avg merge
- 5h 8m
- Merged PRs (30d)
- 1
Description
Hi,
We've had an issue with a parameterised query on SQL Server returning data for the wrong dates. I've found that this parameter:
new DateTime(2019, 11, 20, 23, 59, 59, 999)
actually converts to 2019-11-21 00:00:00 when in fact it should be 2019-11-20 23:59:59.999
Interestingly, new DateTime(2019, 11, 20, 23, 59, 59, 998) converts to 2019-11-20 23:59:59.997.
I'd imagine it's related to the conversion to ticks. This is on 2.0.30.
Thanks
Rob
Contributor guide
No contributing guide indexed for this repository
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the parameterized SQL Server case from the issue, then trace how DateTime values are converted before being sent to the database, focusing on tick and millisecond rounding. Done means 23:59:59.999 remains unchanged, the 998 case remains correct, and a regression test covers both values.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- csharp, sql
- Domain
- databases
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100