From 4d8e1e7cee6fe8321faf21bef907789a502e534a Mon Sep 17 00:00:00 2001
From: FinnTew <nanomoa76@gmail.com>
Date: Sun, 24 Nov 2024 16:59:33 +0800
Subject: [PATCH] optimize: optimize the speed of buildLockKey

---
 .../undo/builder/basic_undo_log_builder.go    | 45 ++++++++++---------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/pkg/datasource/sql/undo/builder/basic_undo_log_builder.go b/pkg/datasource/sql/undo/builder/basic_undo_log_builder.go
index a619c15e4..382384445 100644
--- a/pkg/datasource/sql/undo/builder/basic_undo_log_builder.go
+++ b/pkg/datasource/sql/undo/builder/basic_undo_log_builder.go
@@ -272,35 +272,38 @@ func (b *BasicUndoLogBuilder) buildLockKey(rows driver.Rows, meta types.TableMet
 
 // the string as local key. the local key example(multi pk): "t_user:1_a,2_b"
 func (b *BasicUndoLogBuilder) buildLockKey2(records *types.RecordImage, meta types.TableMeta) string {
-	var (
-		lockKeys      bytes.Buffer
-		filedSequence int
-	)
+	var lockKeys bytes.Buffer
 	lockKeys.WriteString(meta.TableName)
 	lockKeys.WriteString(":")
 
 	keys := meta.GetPrimaryKeyOnlyName()
+	keyIndexMap := make(map[string]int, len(keys))
 
-	for _, row := range records.Rows {
-		if filedSequence > 0 {
-			lockKeys.WriteString(",")
-		}
-		pkSplitIndex := 0
+	for idx, columnName := range keys {
+		keyIndexMap[columnName] = idx
+	}
+
+	primaryKeyRows := make([][]interface{}, len(records.Rows))
+
+	for i, row := range records.Rows {
+		primaryKeyValues := make([]interface{}, len(keys))
 		for _, column := range row.Columns {
-			var hasKeyColumn bool
-			for _, key := range keys {
-				if column.ColumnName == key {
-					hasKeyColumn = true
-					if pkSplitIndex > 0 {
-						lockKeys.WriteString("_")
-					}
-					lockKeys.WriteString(fmt.Sprintf("%v", column.Value))
-					pkSplitIndex++
-				}
+			if idx, exist := keyIndexMap[column.ColumnName]; exist {
+				primaryKeyValues[idx] = column.Value
 			}
-			if hasKeyColumn {
-				filedSequence++
+		}
+		primaryKeyRows[i] = primaryKeyValues
+	}
+
+	for i, primaryKeyValues := range primaryKeyRows {
+		if i > 0 {
+			lockKeys.WriteString(",")
+		}
+		for j, pkVal := range primaryKeyValues {
+			if j > 0 {
+				lockKeys.WriteString("_")
 			}
+			lockKeys.WriteString(fmt.Sprintf("%v", pkVal))
 		}
 	}