Wrong named query support

[rafiwicht]

Hi everyone

Description

First of thanks for the nice package. I have an issue when using the package with sqlx and PostgreSQL. When I use otelsql, sqlx detect the wrong driver type and named queries use ? instead of $1. It also doesn't help to use Rebind.

This doesn't work:

driverName, err := otelsql.Register("pgx",
  otelsql.WithAttributes(semconv.DBSystemNamePostgreSQL),
  otelsql.WithSpanOptions(otelsql.SpanOptions{
    Ping:           true,
    DisableErrSkip: true,
  }),
)
if err != nil {
  return nil, err
}

return sqlx.Open(driverName, config.DBURL), nil

This workaround works:

driverName, err := otelsql.Register("pgx",
  otelsql.WithAttributes(semconv.DBSystemNamePostgreSQL),
  otelsql.WithSpanOptions(otelsql.SpanOptions{
    Ping:           true,
    DisableErrSkip: true,
  }),
)
if err != nil {
  return nil, err
}

db, err := sql.Open(driverName, config.DBURL)
if err != nil {
  return nil, err
}

return sqlx.NewDb(db, "pgx"), nil

Environment

• OS: Linux
• Architecture: x86_64
• Go Version: 1.25.6
• otelsql version: v0.42.0

Steps To Reproduce

1. Use the example from above

Expected behavior

It should work without the workaround.

Let me know what you think. I haven't really looked deeply in your code. If it's a small fix, I canm open an PR.

Best

[XSAM]

Hey @rafiwicht, thanks for creating the issue!

This is a known limitation of otelsql.Register because it returns a new driver name. sqlx has an internal hard-coded DB driver mapping that requires the exact driver name.

https://github.com/jmoiron/sqlx/blob/41dac167fdad5e3fd81d66cafba0951dc6823a30/bind.go#L24-L29

With a custom driver name, sqlx uses UNKNOWN as the bindtype, thus ? stays ?.

https://github.com/jmoiron/sqlx/blob/41dac167fdad5e3fd81d66cafba0951dc6823a30/bind.go#L74-L81

That is why otelsql provides other methods to address compatible issues like this.

In your case, otelsql.Open + sqlx.NewDb(db, "pgx") should work for you.

I will update the doc of otelsql.Register to make this limitation clearer.