planner: fix space requirement when binding from history (pingcap#41140)

close pingcap#41126

infoschema/cluster_tables_test.go

@@ -1264,3 +1264,37 @@ func TestNewCreatedBindingCanWorkWithPlanCache(t *testing.T) {
 	tk.MustExec("execute stmt using @a")
 	tk.MustQuery("select @@last_plan_from_binding").Check(testkit.Rows("1"))
 }
+
+func TestCreateBindingForPrepareToken(t *testing.T) {
+	s := new(clusterTablesSuite)
+	s.store, s.dom = testkit.CreateMockStoreAndDomain(t)
+	s.rpcserver, s.listenAddr = s.setUpRPCService(t, "127.0.0.1:0", nil)
+	s.httpServer, s.mockAddr = s.setUpMockPDHTTPServer()
+	s.startTime = time.Now()
+	defer s.httpServer.Close()
+	defer s.rpcserver.Stop()
+	tk := s.newTestKitWithRoot(t)
+	require.NoError(t, tk.Session().Auth(&auth.UserIdentity{Username: "root", Hostname: "%"}, nil, nil))
+
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t(a int, b time, c varchar(5))")
+
+	//some builtin functions listed in https://dev.mysql.com/doc/refman/8.0/en/function-resolution.html
+	cases := []string{
+		"select std(a) from t",
+		"select cast(a as decimal(10, 2)) from t",
+		"select bit_or(a) from t",
+		"select min(a) from t",
+		"select max(a) from t",
+		"select substr(c, 1, 2) from t",
+	}
+
+	for _, sql := range cases {
+		prep := fmt.Sprintf("prepare stmt from '%s'", sql)
+		tk.MustExec(prep)
+		tk.MustExec("execute stmt")
+		planDigest := tk.MustQuery(fmt.Sprintf("select plan_digest from information_schema.statements_summary where query_sample_text = '%s'", sql)).Rows()
+		tk.MustExec(fmt.Sprintf("create binding from history using plan digest '%s'", planDigest[0][0]))
+	}
+}

util/stmtsummary/statement_summary.go

@@ -515,10 +515,12 @@ func GetBindableStmtFromCluster(rows []chunk.Row) *BindableStmt {
 				Charset:   row.GetString(6), //charset
 				Collation: row.GetString(7), //collation
 			}
-			// If it is SQL command prepare / execute, the ssElement.sampleSQL is `execute ...`, we should get the original select query.
+			// If it is SQL command prepare / execute, we should remove the arguments
 			// If it is binary protocol prepare / execute, ssbd.normalizedSQL should be same as ssElement.sampleSQL.
 			if row.GetInt64(4) == 1 {
-				stmt.Query = row.GetString(2) //normalizedSQL
+				if idx := strings.LastIndex(stmt.Query, "[arguments:"); idx != -1 {
+					stmt.Query = stmt.Query[:idx]
+				}
 			}
 			return stmt
 		}