DapperLib / DapperLib/Dapper

PackListParameters should check `IEnumerable<DbString>` before FeatureSupport.Arrays

Open
#1,193 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
C#
Stars
18.4k
Forks
3.7k
Avg merge
5h 8m
Merged PRs (30d)
1

Description

Dapper: 1.50.7

https://github.com/StackExchange/Dapper/blob/1.50.7/Dapper/SqlMapper.cs#L1975
Dapper.DbString[] should not be directly send to PostgreSQL or other server in the case at least.

Edited: In fact, it's no needed to use IEnumerable<DbString> in PostgreSQL, just hit this during migrate between databases.


BTW: Seems there is another limit for PostgreSQL, only IList or T[] is supported for npgsql >= 3.0, and not for IEnumerable/IList. But can be easily workaround by user code.

System.NotSupportedException: 'Npgsql 3.x removed support for writing a parameter with an IEnumerable value, use .ToList()/.ToArray() instead'

https://github.com/npgsql/npgsql/blob/v4.0.4.1/src/Npgsql/TypeMapping/ConnectorTypeMapper.cs#L155

https://github.com/npgsql/npgsql/blob/v4.0.4.1/src/Npgsql/TypeMapping/ConnectorTypeMapper.cs#L117

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start at Dapper/SqlMapper.cs around line 1975 and read PackListParameters alongside the linked PostgreSQL and Npgsql behavior. Verify the parameter handling for DbString arrays or enumerables across the relevant database cases, then confirm the resulting behavior against the reported Npgsql limitations.

Written by the indexing model from the issue text.

Assessment

Tech stack
csharp, postgresql
Domain
databases
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.