resolve conflicts

executor/show.go

@@ -668,6 +668,9 @@ func (e *ShowExec) fetchShowVariables() (err error) {
 		unreachedVars = make([]string, 0, len(variable.GetSysVars()))
 	)
 	for _, v := range variable.GetSysVars() {
+		if variable.FilterImplicitFeatureSwitch(v.Name) {
+			continue
+		}
 		if !e.GlobalScope {
 			// For a session scope variable,
 			// 1. try to fetch value from SessionVars.Systems;
@@ -695,6 +698,9 @@ func (e *ShowExec) fetchShowVariables() (err error) {
 			return errors.Trace(err)
 		}
 		for _, varName := range unreachedVars {
+			if variable.FilterImplicitFeatureSwitch(varName) {
+				continue
+			}
 			varValue, ok := systemVars[varName]
 			if !ok {
 				varValue = variable.GetSysVar(varName).Value

executor/show_test.go

@@ -1242,11 +1242,10 @@ func (s *testSerialSuite1) TestShowCreateTableWithIntegerDisplayLengthWarnings(c
 
 func (s *testSuite5) TestShowVar(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
-	var showSQL string
 	sessionVars := make([]string, 0, len(variable.GetSysVars()))
 	globalVars := make([]string, 0, len(variable.GetSysVars()))
 	for _, v := range variable.GetSysVars() {
-		if variable.FilterImplicitFeatureSwitch(v) {
+		if variable.FilterImplicitFeatureSwitch(v.Name) {
 			continue
 		}
 
@@ -1257,23 +1256,6 @@ func (s *testSuite5) TestShowVar(c *C) {
 		}
 	}
 
-	// When ScopeSession only. `show global variables` must return empty.
-	sessionVarsStr := strings.Join(sessionVars, "','")
-	showSQL = "show variables where variable_name in('" + sessionVarsStr + "')"
-	res := tk.MustQuery(showSQL)
-	c.Check(res.Rows(), HasLen, len(sessionVars))
-	showSQL = "show global variables where variable_name in('" + sessionVarsStr + "')"
-	res = tk.MustQuery(showSQL)
-	c.Check(res.Rows(), HasLen, 0)
-
-	globalVarsStr := strings.Join(globalVars, "','")
-	showSQL = "show variables where variable_name in('" + globalVarsStr + "')"
-	res = tk.MustQuery(showSQL)
-	c.Check(res.Rows(), HasLen, len(globalVars))
-	showSQL = "show global variables where variable_name in('" + globalVarsStr + "')"
-	res = tk.MustQuery(showSQL)
-	c.Check(res.Rows(), HasLen, len(globalVars))
-
 	// Test for switch variable which shouldn't seen by users.
 	for _, one := range variable.FeatureSwitchVariables {
 		res := tk.MustQuery("show variables like '" + one + "'")

session/session.go

@@ -949,7 +949,13 @@ func (s *session) GetAllSysVars() (map[string]string, error) {
 	ret := make(map[string]string, len(rows))
 	for _, r := range rows {
 		k, v := r.GetString(0), r.GetString(1)
-		ret[k] = v
+		if s.varFromTiDBTable(k) {
+			if v, err = s.getTiDBTableValue(k, v); err == nil {
+				ret[k] = v
+			}
+		} else {
+			ret[k] = v
+		}
 	}
 	return ret, nil
 }

sessionctx/variable/tidb_vars.go

@@ -742,9 +742,9 @@ var FeatureSwitchVariables = []string{
 }
 
 // FilterImplicitFeatureSwitch is used to filter result of show variables, these switches should be turn blind to users.
-func FilterImplicitFeatureSwitch(sysVar *SysVar) bool {
+func FilterImplicitFeatureSwitch(varName string) bool {
 	for _, one := range FeatureSwitchVariables {
-		if one == sysVar.Name {
+		if one == varName {
 			return true
 		}
 	}