From 4f7f3ab4cbef5a4ad45ec5257d50522362529271 Mon Sep 17 00:00:00 2001
From: Ti Chi Robot <ti-community-prow-bot@tidb.io>
Date: Wed, 28 Jun 2023 08:38:35 +0800
Subject: [PATCH] executor: avoid using fmt.Sprint to truncate the string
 (#44540) (#44557)

close pingcap/tidb#44542
---
 executor/adapter.go                   | 6 +++++-
 executor/adapter_test.go              | 2 +-
 util/stmtsummary/statement_summary.go | 5 ++++-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/executor/adapter.go b/executor/adapter.go
index 59fe7d30cd38b..33a30af2a2112 100644
--- a/executor/adapter.go
+++ b/executor/adapter.go
@@ -1199,7 +1199,11 @@ func FormatSQL(sql string) stringutil.StringerFunc {
 			return QueryReplacer.Replace(sql) // no limit
 		}
 		if int32(length) > maxQueryLen {
-			sql = fmt.Sprintf("%.*q(len:%d)", maxQueryLen, sql, length)
+			var result strings.Builder
+			result.Grow(int(maxQueryLen))
+			result.WriteString(sql[:maxQueryLen])
+			fmt.Fprintf(&result, "(len:%d)", length)
+			return QueryReplacer.Replace(result.String())
 		}
 		return QueryReplacer.Replace(sql)
 	}
diff --git a/executor/adapter_test.go b/executor/adapter_test.go
index 1e28472a72bfb..012075c8e4a0c 100644
--- a/executor/adapter_test.go
+++ b/executor/adapter_test.go
@@ -50,5 +50,5 @@ func TestFormatSQL(t *testing.T) {
 	require.Equal(t, "aaaaaaaaaaaaaaaaaaaa", val.String())
 	variable.QueryLogMaxLen.Store(5)
 	val = executor.FormatSQL("aaaaaaaaaaaaaaaaaaaa")
-	require.Equal(t, "\"aaaaa\"(len:20)", val.String())
+	require.Equal(t, "aaaaa(len:20)", val.String())
 }
diff --git a/util/stmtsummary/statement_summary.go b/util/stmtsummary/statement_summary.go
index 6740656c9ca9e..41238e088d68e 100644
--- a/util/stmtsummary/statement_summary.go
+++ b/util/stmtsummary/statement_summary.go
@@ -908,7 +908,10 @@ func formatSQL(sql string) string {
 	maxSQLLength := StmtSummaryByDigestMap.maxSQLLength()
 	length := len(sql)
 	if length > maxSQLLength {
-		sql = fmt.Sprintf("%.*s(len:%d)", maxSQLLength, sql, length)
+		var result strings.Builder
+		result.WriteString(sql[:maxSQLLength])
+		fmt.Fprintf(&result, "(len:%d)", length)
+		return result.String()
 	}
 	return sql
 }