From c5ad5640e38b0f2e0b5fd7f55f898aeb5c2957da Mon Sep 17 00:00:00 2001
From: "vitess-bot[bot]" <108069721+vitess-bot[bot]@users.noreply.github.com>
Date: Wed, 3 Dec 2025 01:19:04 -0500
Subject: [PATCH] vdiff: do not sort by table name in summary, it is not
 necessary (#18972)

Signed-off-by: Nick Van Wiggeren <nick@planetscale.com>
---
 .../command/vreplication/vdiff/vdiff.go       |  2 +-
 go/vt/vtctl/workflow/vdiff.go                 | 16 +++++++++++
 go/vt/vtctl/workflow/vdiff_test.go            | 27 +++++++++++++++++++
 go/vt/vttablet/tabletmanager/vdiff/schema.go  |  2 +-
 4 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/go/cmd/vtctldclient/command/vreplication/vdiff/vdiff.go b/go/cmd/vtctldclient/command/vreplication/vdiff/vdiff.go
index 94147fd3550..f980dcf699e 100644
--- a/go/cmd/vtctldclient/command/vreplication/vdiff/vdiff.go
+++ b/go/cmd/vtctldclient/command/vreplication/vdiff/vdiff.go
@@ -438,7 +438,7 @@ HasMismatch:  {{.HasMismatch}}
 StartedAt:    {{.StartedAt}}
 {{if (eq .State "started")}}Progress:     {{printf "%.2f" .Progress.Percentage}}%{{if .Progress.ETA}}, ETA: {{.Progress.ETA}}{{end}}{{end}}
 {{if .CompletedAt}}CompletedAt:  {{.CompletedAt}}{{end}}
-{{range $table := .TableSummaryMap}} 
+{{range $table := .SortedTableSummaries}} 
 Table {{$table.TableName}}:
 	State:            {{$table.State}}
 	ProcessedRows:    {{$table.RowsCompared}}
diff --git a/go/vt/vtctl/workflow/vdiff.go b/go/vt/vtctl/workflow/vdiff.go
index 30953868b0b..ab5d50c1489 100644
--- a/go/vt/vtctl/workflow/vdiff.go
+++ b/go/vt/vtctl/workflow/vdiff.go
@@ -69,6 +69,22 @@ type Summary struct {
 	Progress *vdiff.ProgressReport `json:"Progress,omitempty"`
 }
 
+// SortedTableSummaries returns the table summaries sorted alphabetically by table name.
+// This is used by text templates to display tables in a consistent order.
+func (s *Summary) SortedTableSummaries() []TableSummary {
+	names := make([]string, 0, len(s.TableSummaryMap))
+	for name := range s.TableSummaryMap {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+
+	result := make([]TableSummary, 0, len(names))
+	for _, name := range names {
+		result = append(result, s.TableSummaryMap[name])
+	}
+	return result
+}
+
 // BuildSummary generates a summary from a vdiff show response.
 func BuildSummary(keyspace, workflow, uuid string, resp *vtctldatapb.VDiffShowResponse, verbose bool) (*Summary, error) {
 	summary := &Summary{
diff --git a/go/vt/vtctl/workflow/vdiff_test.go b/go/vt/vtctl/workflow/vdiff_test.go
index 0da4a3ef480..9c2c5cca77a 100644
--- a/go/vt/vtctl/workflow/vdiff_test.go
+++ b/go/vt/vtctl/workflow/vdiff_test.go
@@ -34,6 +34,33 @@ import (
 	vtctldatapb "vitess.io/vitess/go/vt/proto/vtctldata"
 )
 
+func TestSortedTableSummaries(t *testing.T) {
+	summary := &Summary{
+		TableSummaryMap: map[string]TableSummary{
+			"zebra": {TableName: "zebra"},
+			"apple": {TableName: "apple"},
+			"mango": {TableName: "mango"},
+		},
+	}
+
+	sorted := summary.SortedTableSummaries()
+
+	require.Len(t, sorted, 3)
+	require.Equal(t, "apple", sorted[0].TableName)
+	require.Equal(t, "mango", sorted[1].TableName)
+	require.Equal(t, "zebra", sorted[2].TableName)
+}
+
+func TestSortedTableSummariesEmpty(t *testing.T) {
+	summary := &Summary{
+		TableSummaryMap: map[string]TableSummary{},
+	}
+
+	sorted := summary.SortedTableSummaries()
+
+	require.Len(t, sorted, 0)
+}
+
 func TestBuildProgressReport(t *testing.T) {
 	now := time.Now()
 	type args struct {
diff --git a/go/vt/vttablet/tabletmanager/vdiff/schema.go b/go/vt/vttablet/tabletmanager/vdiff/schema.go
index 9fef975e1e0..bb238cb8a7a 100644
--- a/go/vt/vttablet/tabletmanager/vdiff/schema.go
+++ b/go/vt/vttablet/tabletmanager/vdiff/schema.go
@@ -40,7 +40,7 @@ const (
 						vd.started_at as started_at, vdt.rows_compared as rows_compared, vd.completed_at as completed_at,
 						IF(vdt.mismatch = 1, 1, 0) as has_mismatch, vdt.report as report
 						from _vt.vdiff as vd left join _vt.vdiff_table as vdt on (vd.id = vdt.vdiff_id)
-						where vd.id = %a order by table_name`
+						where vd.id = %a`
 	// sqlUpdateVDiffState has a penultimate placeholder for any additional columns you want to update, e.g. `, foo = 1`.
 	// It also truncates the error if needed to ensure that we can save the state when the error text is very long.
 	sqlUpdateVDiffState   = "update _vt.vdiff set state = %s, last_error = left(%s, 1024) %s where id = %d"