Writing bytes to String column fails (INTERNAL EXCEPTION WHILE SERIALIZING)

[TimNooren]

Writing bytes to a String column fails with INTERNAL EXCEPTION WHILE SERIALIZING. Writing bytes to FixedString works as expected, so I assume the same should be possible with String columns. But I'm very new to Clickhouse, so I may have missed something:)

Steps to reproduce

See main...TimNooren:clickhouse-connect:string_accepts_bytes for a unit test that illustrates the issue, and a naive fix.

Configuration

Environment

• clickhouse-connect version: 0.5.15
• Python version: 3.11.12
• Operating system: macOS (ARM)

[genzgd]

Thanks for opening this issue and taking the time to investigate a fix. Accepting bytes for a string column makes perfect sense and I'm surprised no one has mentioned it before.

My only concern with your fix is performance, since string writes are already slow and an extra type check and assignment are going to make that slightly worse. But I can address that later as part of #106. For a short term fix I'm inclined to use the same approach as other columns, and assume that all values in the column are the same type as the first (non-NULL) value and write all strings or all bytes objects as appropriate.

[TimNooren]

@genzgd Makes sense to at least use the same approach as for FixedString👍 Would be happy to submit a PR, but I see you already covered it. Thanks:)