How to log batched SQL queries?

[benjamin-bader]

Hi there!

I'm working with logging at the moment, and noticing that in the v4 Logger interface, I see SQL text in the data map under the "sql" key. For batched queries, unfortunately, it seems that this field is always the literal value "batch query".

Is there a way, in pgx, to log the individual statements that make up a batch?

My log configuration code, in essence:

func (la *LogAdapter) Log(ctx context.Context, level pgx.LogLevel, msg string, data map[string]interface{}) {
  if sql, ok := data["sql"]; ok {
    la.logger.Infof("Executing SQL: %s", sql)
  }
}

config, err := pgxpool.ParseConfig(...)
// error handling omitted
config.ConnConfig.Logger = &LogAdapter{...}

[jackc]

There's currently no way do this. The batchResults struct doesn't know what was sent to the server. I suppose it could keep a reference to the original batch and match up based on the order the results come back. The timing measurements would still be off though.

[benjamin-bader]

That's a good point re:timing; I hadn't considered that since we usually get query timings from other sources, e.g. pg_stat_statements.

Would you be open to a PR that added this logging? Naively, it seems like a simple-enough bit of state-threading.

[jackc]

Would you be open to a PR that added this logging?

Sure.