*: fixed some typo. (#7277)

executor/executor_test.go

@@ -1594,7 +1594,7 @@ func (s *testSuite) TestSQLMode(c *C) {
 	tk.MustExec("set sql_mode = 'STRICT_TRANS_TABLES'")
 	tk.MustExec("set @@global.sql_mode = ''")
 
-	// With the existance of global variable cache, it have to sleep a while here.
+	// With the existence of global variable cache, it have to sleep a while here.
 	time.Sleep(3 * time.Second)
 	tk2 := testkit.NewTestKit(c, s.store)
 	tk2.MustExec("use test")
@@ -2845,7 +2845,7 @@ func (s *testSuite) TestForSelectScopeInUnion(c *C) {
 	tk2.MustExec("use test")
 	tk2.MustExec("update t set a = a + 1")
 
-	// As tk1 use select 'for update', it should dectect conflict and fail.
+	// As tk1 use select 'for update', it should detect conflict and fail.
 	_, err := tk1.Exec("commit")
 	c.Assert(err, NotNil)
 

metrics/ddl.go

@@ -101,13 +101,13 @@ var (
 			Help:      "Counter of creating ddl/worker and isowner.",
 		}, []string{LblType})
 
-	// DDLJobErrCounter is the counter of error occured in ddl job.
+	// DDLJobErrCounter is the counter of error occurred in ddl job.
 	DDLJobErrCounter = prometheus.NewCounter(
 		prometheus.CounterOpts{
 			Namespace: "tidb",
 			Subsystem: "ddl",
 			Name:      "job_error_total",
-			Help:      "Counter of error occured in ddl job.",
+			Help:      "Counter of error occurred in ddl job.",
 		})
 )
 

session/session_test.go

@@ -1955,7 +1955,7 @@ func (s *testSessionSuite) TestSetGlobalTZ(c *C) {
 
 	tk.MustQuery("show variables like 'time_zone'").Check(testkit.Rows("time_zone +08:00"))
 
-	// With the existance of global variable cache, it have to sleep a while here.
+	// With the existence of global variable cache, it have to sleep a while here.
 	time.Sleep(3 * time.Second)
 	tk1 := testkit.NewTestKitWithInit(c, s.store)
 	tk1.MustQuery("show variables like 'time_zone'").Check(testkit.Rows("time_zone +00:00"))

tablecodec/tablecodec.go

@@ -222,7 +222,7 @@ func EncodeValue(sc *stmtctx.StatementContext, raw types.Datum) ([]byte, error)
 
 // EncodeRow encode row data and column ids into a slice of byte.
 // Row layout: colID1, value1, colID2, value2, .....
-// valBuf and values pass by caller, for reducing EncodeRow allocates tempory bufs. If you pass valBuf and values as nil,
+// valBuf and values pass by caller, for reducing EncodeRow allocates temporary bufs. If you pass valBuf and values as nil,
 // EncodeRow will allocate it.
 func EncodeRow(sc *stmtctx.StatementContext, row []types.Datum, colIDs []int64, valBuf []byte, values []types.Datum) ([]byte, error) {
 	if len(row) != len(colIDs) {