Fix CommandTag RowsAffected for INSERT

conn.go

@@ -83,12 +83,8 @@ type CommandTag string
 // RowsAffected returns the number of rows affected. If the CommandTag was not
 // for a row affecting command (such as "CREATE TABLE") then it returns 0
 func (ct CommandTag) RowsAffected() int64 {
-	words := strings.SplitN(string(ct), " ", 2)
-	if len(words) != 2 {
-		return 0
-	}
-
-	n, _ := strconv.ParseInt(words[1], 10, 64)
+	words := strings.Split(string(ct), " ")
+	n, _ := strconv.ParseInt(words[len(words)-1], 10, 64)
 	return n
 }
 

conn_test.go

@@ -860,6 +860,7 @@ func TestCommandTag(t *testing.T) {
 		commandTag   pgx.CommandTag
 		rowsAffected int64
 	}{
+		{commandTag: "INSERT 0 5", rowsAffected: 5},
 		{commandTag: "UPDATE 0", rowsAffected: 0},
 		{commandTag: "UPDATE 1", rowsAffected: 1},
 		{commandTag: "DELETE 0", rowsAffected: 0},