import (
    "github.com/VictoriaMetrics/metrics"
    "github.com/cristalhq/sqlmetrics"
)

// ...

db, err := sql.Open("<some-connection-string>")
if err != nil {
    panic(err)
}

ctx := context.Background() // or any other context you have
every := 3 * time.Second

sqlmetrics.NewCollector(ctx, db, every, "label1", "value1", "another", "etc")

// done, db metrics are registered
// you can see them here
w := &bytes.Buffer{}
metrics.WritePrometheus(w, true)