derived table and row number addition

playground/db/derived.go

@@ -0,0 +1,11 @@
+package db
+
+import "code.patial.tech/go/pgm"
+
+func DerivedTable(tblName string, fromQry pgm.Query) pgm.Table {
+	t := pgm.Table{
+		Name:         tblName,
+		DerivedTable: fromQry,
+	}
+	return t
+}