Support single db select order by. (arana-db#163)

IoCing · May 21, 2022 · 2cf11cd · 2cf11cd
1 parent f8c6c9d
commit 2cf11cd
Showing 1 changed file with 31 additions and 0 deletions.
diff --git a/pkg/runtime/plan/simple_select.go b/pkg/runtime/plan/simple_select.go
@@ -140,7 +140,38 @@ func (s *SimpleQueryPlan) generate(sb *strings.Builder, args *[]int) error {
 				return errors.WithStack(err)
 			}
 		}
+
+		if len(stmt.OrderBy) > 0 {
+			s.resetOrderBy(s.Stmt, sb, args)
+		}
 	}
 
 	return nil
 }
+
+func (s *SimpleQueryPlan) resetOrderBy(tgt *ast.SelectStatement, sb *strings.Builder, args *[]int) error {
+	var (
+		builder strings.Builder
+	)
+	builder.WriteString("SELECT * FROM (")
+	builder.WriteString(sb.String())
+	builder.WriteString(") ")
+	if len(tgt.From[0].Alias()) > 0 {
+		builder.WriteString(tgt.From[0].Alias())
+	} else {
+		builder.WriteString(" T ")
+	}
+	builder.WriteString(" ORDER BY ")
+	if err := tgt.OrderBy[0].Restore(ast.RestoreDefault, &builder, args); err != nil {
+		return errors.WithStack(err)
+	}
+	for i := 1; i < len(tgt.OrderBy); i++ {
+		builder.WriteString(", ")
+		if err := tgt.OrderBy[i].Restore(ast.RestoreDefault, &builder, args); err != nil {
+			return errors.WithStack(err)
+		}
+	}
+	sb.Reset()
+	sb.WriteString(builder.String())
+	return nil
+}