Introduce own Numeric type and revert to stdlib from pgx

postgres/numeric.go

@@ -0,0 +1,21 @@
+package postgres
+
+import "github.com/jackc/pgtype"
+
+type Numeric struct {
+	pgtype.Numeric
+}
+
+func (n Numeric) GetFloat64() float64 {
+	var balance float64
+	err := n.AssignTo(&balance)
+	if err != nil {
+		panic(err)
+	}
+	return balance
+}
+
+func (n Numeric) GetPositive() bool {
+	float := n.GetFloat64()
+	return float >= 0
+}