Merge branch 'master' into convert-bug

.build.ps1

@@ -154,7 +154,7 @@ task DownloadLinter -If (-not (Test-Path $tools.Linter.Path)) {
 }
 
 task RunLinter DownloadLinter, {
-    exec { & $tools.Linter.Path run -v --disable-all --deadline=3m --enable=misspell --enable=ineffassign $directories }
+    exec { & $tools.Linter.Path run -v --disable-all --deadline=3m --enable=misspell --enable=ineffassign --enable=varcheck $directories }
 }
 
 task GoModTidy {

Makefile

@@ -52,6 +52,7 @@ check-static: tools/bin/golangci-lint
 	tools/bin/golangci-lint run -v --disable-all --deadline=3m \
 	  --enable=misspell \
 	  --enable=ineffassign \
+	  --enable=varcheck \
 	  $$($(PACKAGE_DIRECTORIES))
 
 check-slow:tools/bin/gometalinter tools/bin/gosec

cmd/ddltest/ddl_test.go

@@ -97,11 +97,11 @@ type TestDDLSuite struct {
 }
 
 func (s *TestDDLSuite) SetUpSuite(c *C) {
-	logutil.InitLogger(&logutil.LogConfig{Config: zaplog.Config{Level: *logLevel}})
+	err := logutil.InitLogger(&logutil.LogConfig{Config: zaplog.Config{Level: *logLevel}})
+	c.Assert(err, IsNil)
 
 	s.quit = make(chan struct{})
 
-	var err error
 	s.store, err = store.New(fmt.Sprintf("tikv://%s%s", *etcd, *tikvPath))
 	c.Assert(err, IsNil)
 
@@ -304,7 +304,11 @@ func (s *TestDDLSuite) startServer(i int, fp *os.File) (*server, error) {
 		}
 		log.Warnf("ping addr %v failed, retry count %d err %v", addr, i, err)
 
-		db.Close()
+		err = db.Close()
+		if err != nil {
+			log.Warnf("close db failed, retry count %d err %v", i, err)
+			break
+		}
 		time.Sleep(sleepTime)
 		sleepTime += sleepTime
 	}

cmd/ddltest/index_test.go

@@ -64,7 +64,8 @@ func (s *TestDDLSuite) checkAddIndex(c *C, indexInfo *model.IndexInfo) {
 	txn, err := ctx.Txn(false)
 	c.Assert(err, IsNil)
 	defer func() {
-		txn.Rollback()
+		err = txn.Rollback()
+		c.Assert(err, IsNil)
 	}()
 
 	it, err := idx.SeekFirst(txn)
@@ -103,7 +104,10 @@ func (s *TestDDLSuite) checkDropIndex(c *C, indexInfo *model.IndexInfo) {
 	c.Assert(err, IsNil)
 	txn, err := ctx.Txn(false)
 	c.Assert(err, IsNil)
-	defer txn.Rollback()
+	defer func(){
+		err := txn.Rollback()
+		c.Assert(err, IsNil)
+	}()
 
 	it, err := idx.SeekFirst(txn)
 	c.Assert(err, IsNil)

cmd/explaintest/r/generated_columns.result

@@ -1,4 +1,4 @@
-set @@tidb_partition_prune_mode='dynamic-only';
+set @@tidb_partition_prune_mode='dynamic';
 DROP TABLE IF EXISTS person;
 CREATE TABLE person (
 id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,

cmd/explaintest/t/generated_columns.test

@@ -2,7 +2,7 @@
 -- Most of the cases are ported from other tests to make sure generated columns behaves the same.
 
 -- Stored generated columns as indices
-set @@tidb_partition_prune_mode='dynamic-only';
+set @@tidb_partition_prune_mode='dynamic';
 
 DROP TABLE IF EXISTS person;
 CREATE TABLE person (

config/config_test.go

@@ -108,8 +108,10 @@ func (s *testConfigSuite) TestLogConfig(c *C) {
 		c.Assert(conf.Log.EnableTimestamp, Equals, expectedEnableTimestamp)
 		c.Assert(conf.Log.DisableTimestamp, Equals, expectedDisableTimestamp)
 		c.Assert(conf.Log.ToLogConfig(), DeepEquals, logutil.NewLogConfig("info", "text", "tidb-slow.log", conf.Log.File, resultedDisableTimestamp, func(config *zaplog.Config) { config.DisableErrorVerbose = resultedDisableErrorVerbose }))
-		f.Truncate(0)
-		f.Seek(0, 0)
+		err := f.Truncate(0)
+		c.Assert(err, IsNil)
+		_, err = f.Seek(0, 0)
+		c.Assert(err, IsNil)
 	}
 
 	testLoad(`
@@ -174,8 +176,10 @@ unrecognized-option-test = true
 	c.Assert(conf.Load(configFile), ErrorMatches, "(?:.|\n)*invalid configuration option(?:.|\n)*")
 	c.Assert(conf.MaxServerConnections, Equals, uint32(0))
 
-	f.Truncate(0)
-	f.Seek(0, 0)
+	err = f.Truncate(0)
+	c.Assert(err, IsNil)
+	_, err = f.Seek(0, 0)
+	c.Assert(err, IsNil)
 
 	_, err = f.WriteString(`
 token-limit = 0
@@ -286,8 +290,10 @@ log-rotate = true`)
 
 	// Test telemetry config default value and whether it will be overwritten.
 	conf = NewConfig()
-	f.Truncate(0)
-	f.Seek(0, 0)
+	err = f.Truncate(0)
+	c.Assert(err, IsNil)
+	_, err = f.Seek(0, 0)
+	c.Assert(err, IsNil)
 	c.Assert(f.Sync(), IsNil)
 	c.Assert(conf.Load(configFile), IsNil)
 	c.Assert(conf.EnableTelemetry, Equals, true)

config/config_util.go

@@ -25,6 +25,7 @@ import (
 
 	"github.com/BurntSushi/toml"
 	"github.com/pingcap/errors"
+	"github.com/pingcap/failpoint"
 )
 
 // CloneConf deeply clones this config.
@@ -161,6 +162,13 @@ const (
 
 // GetTxnScopeFromConfig extracts @@txn_scope value from config
 func GetTxnScopeFromConfig() (bool, string) {
+	failpoint.Inject("injectTxnScope", func(val failpoint.Value) {
+		v := val.(string)
+		if len(v) > 0 {
+			failpoint.Return(false, v)
+		}
+		failpoint.Return(true, globalTxnScope)
+	})
 	v, ok := GetGlobalConfig().Labels["zone"]
 	if ok && len(v) > 0 {
 		return false, v

config/config_util_test.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/BurntSushi/toml"
 	. "github.com/pingcap/check"
+	"github.com/pingcap/failpoint"
 )
 
 func (s *testConfigSuite) TestCloneConf(c *C) {
@@ -170,16 +171,19 @@ engines = ["tikv", "tiflash", "tidb"]
 }
 
 func (s *testConfigSuite) TestTxnScopeValue(c *C) {
-	GetGlobalConfig().Labels["zone"] = "bj"
+	failpoint.Enable("github.com/pingcap/tidb/config/injectTxnScope", `return("bj")`)
 	isGlobal, v := GetTxnScopeFromConfig()
 	c.Assert(isGlobal, IsFalse)
 	c.Assert(v, Equals, "bj")
-	GetGlobalConfig().Labels["zone"] = ""
+	failpoint.Disable("github.com/pingcap/tidb/config/injectTxnScope")
+	failpoint.Enable("github.com/pingcap/tidb/config/injectTxnScope", `return("")`)
 	isGlobal, v = GetTxnScopeFromConfig()
 	c.Assert(isGlobal, IsTrue)
 	c.Assert(v, Equals, "global")
-	GetGlobalConfig().Labels["zone"] = "global"
+	failpoint.Disable("github.com/pingcap/tidb/config/injectTxnScope")
+	failpoint.Enable("github.com/pingcap/tidb/config/injectTxnScope", `return("global")`)
 	isGlobal, v = GetTxnScopeFromConfig()
 	c.Assert(isGlobal, IsFalse)
 	c.Assert(v, Equals, "global")
+	failpoint.Disable("github.com/pingcap/tidb/config/injectTxnScope")
 }

ddl/error.go

@@ -53,7 +53,6 @@ var (
 	errIncorrectPrefixKey                     = dbterror.ClassDDL.NewStd(mysql.ErrWrongSubKey)
 	errTooLongKey                             = dbterror.ClassDDL.NewStd(mysql.ErrTooLongKey)
 	errKeyColumnDoesNotExits                  = dbterror.ClassDDL.NewStd(mysql.ErrKeyColumnDoesNotExits)
-	errUnknownTypeLength                      = dbterror.ClassDDL.NewStd(mysql.ErrUnknownTypeLength)
 	errInvalidDDLJobVersion                   = dbterror.ClassDDL.NewStd(mysql.ErrInvalidDDLJobVersion)
 	errInvalidUseOfNull                       = dbterror.ClassDDL.NewStd(mysql.ErrInvalidUseOfNull)
 	errTooManyFields                          = dbterror.ClassDDL.NewStd(mysql.ErrTooManyFields)

ddl/placement_sql_test.go

@@ -18,8 +18,8 @@ import (
 	"sort"
 
 	. "github.com/pingcap/check"
+	"github.com/pingcap/failpoint"
 	"github.com/pingcap/parser/model"
-	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/ddl"
 	"github.com/pingcap/tidb/ddl/placement"
 	"github.com/pingcap/tidb/session"
@@ -440,9 +440,6 @@ func (s *testDBSuite1) TestPlacementPolicyCache(c *C) {
 }
 
 func (s *testSerialDBSuite) TestTxnScopeConstraint(c *C) {
-	defer func() {
-		config.GetGlobalConfig().Labels["zone"] = ""
-	}()
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists t1")
@@ -569,9 +566,8 @@ PARTITION BY RANGE (c) (
 
 	for _, testcase := range testCases {
 		c.Log(testcase.name)
-		config.GetGlobalConfig().Labels = map[string]string{
-			"zone": testcase.zone,
-		}
+		failpoint.Enable("github.com/pingcap/tidb/config/injectTxnScope",
+			fmt.Sprintf(`return("%v")`, testcase.zone))
 		se, err := session.CreateSession4Test(s.store)
 		c.Check(err, IsNil)
 		tk.Se = se
@@ -591,6 +587,7 @@ PARTITION BY RANGE (c) (
 			c.Assert(err, NotNil)
 			c.Assert(err.Error(), Matches, testcase.err.Error())
 		}
+		failpoint.Disable("github.com/pingcap/tidb/config/injectTxnScope")
 	}
 }
 
@@ -661,9 +658,6 @@ add placement policy
 }
 
 func (s *testSerialSuite) TestGlobalTxnState(c *C) {
-	defer func() {
-		config.GetGlobalConfig().Labels["zone"] = ""
-	}()
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists t1")
@@ -704,9 +698,8 @@ PARTITION BY RANGE (c) (
 			},
 		},
 	}
-	config.GetGlobalConfig().Labels = map[string]string{
-		"zone": "bj",
-	}
+	failpoint.Enable("github.com/pingcap/tidb/config/injectTxnScope", `return("bj")`)
+	defer failpoint.Disable("github.com/pingcap/tidb/config/injectTxnScope")
 	dbInfo := testGetSchemaByName(c, tk.Se, "test")
 	tk2 := testkit.NewTestKit(c, s.store)
 	var chkErr error

docs/tidb_http_api.md

@@ -200,6 +200,37 @@
     }
     ```
 
+    If the handle is clustered, specify the primary key column values in the query string
+
+    ```shell
+    $curl http://{TiDBIP}:10080/mvcc/key/{db}/{table}?${c1}={v1}&${c2}=${v2}
+    ```
+
+    ```shell
+    $curl http://127.0.0.1:10080/mvcc/key/test/t\?a\=aaa\&b\=2020-01-01
+    {
+        "key": "7480000000000000365F72016161610000000000FA0419A5420000000000",
+        "region_id": 52,
+        "value": {
+            "info": {
+                "writes": [
+                    {
+                        "start_ts": 423158426542538752,
+                        "commit_ts": 423158426543587328,
+                        "short_value": "gAACAAAAAQMDAAQAYWFhZA=="
+                    }
+                ],
+                "values": [
+                    {
+                        "start_ts": 423158426542538752,
+                        "value": "gAACAAAAAQMDAAQAYWFhZA=="
+                    }
+                ]
+            }
+        }
+    }
+    ```
+
 1. Get MVCC Information of the first key in the table with a specified start ts
 
     ```shell

domain/infosync/info.go

@@ -82,9 +82,6 @@ const (
 // ErrPrometheusAddrIsNotSet is the error that Prometheus address is not set in PD and etcd
 var ErrPrometheusAddrIsNotSet = dbterror.ClassDomain.NewStd(errno.ErrPrometheusAddrIsNotSet)
 
-// errPlacementRulesDisabled is exported for internal usage, indicating PD rejected the request due to disabled placement feature.
-var errPlacementRulesDisabled = errors.New("placement rules feature is disabled")
-
 // InfoSyncer stores server info to etcd when the tidb-server starts and delete when tidb-server shuts down.
 type InfoSyncer struct {
 	etcdCli         *clientv3.Client

errno/errcode.go

@@ -991,6 +991,7 @@ const (
 	ErrInvalidTableSample                  = 8128
 	ErrJSONObjectKeyTooLong                = 8129
 	ErrMultiStatementDisabled              = 8130
+	ErrBuildGlobalLevelStatsFailed         = 8131
 
 	// Error codes used by TiDB ddl package
 	ErrUnsupportedDDLOperation            = 8200

errno/errname.go

@@ -1032,7 +1032,8 @@ var MySQLErrName = map[uint16]*mysql.ErrMessage{
 
 	ErrInvalidTableSample: mysql.Message("Invalid TABLESAMPLE: %s", nil),
 
-	ErrJSONObjectKeyTooLong: mysql.Message("TiDB does not yet support JSON objects with the key length >= 65536", nil),
+	ErrJSONObjectKeyTooLong:        mysql.Message("TiDB does not yet support JSON objects with the key length >= 65536", nil),
+	ErrBuildGlobalLevelStatsFailed: mysql.Message("Build global-level stats failed due to missing partition-level stats", nil),
 
 	ErrInvalidPlacementSpec:   mysql.Message("Invalid placement policy '%s': %s", nil),
 	ErrPlacementPolicyCheck:   mysql.Message("Placement policy didn't meet the constraint, reason: %s", nil),

errors.toml

@@ -1571,6 +1571,11 @@ error = '''
 TiDB does not yet support JSON objects with the key length >= 65536
 '''
 
+["types:8131"]
+error = '''
+Build global-level stats failed due to missing partition-level stats
+'''
+
 ["variable:1193"]
 error = '''
 Unknown system variable '%-.64s'