Golang sql.MakeDescMetadataKey函數代碼示例

func TestInsert(t *testing.T) {
	defer leaktest.AfterTest(t)
	s, sqlDB, kvDB := setup(t)
	defer cleanup(s, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.kv (
  k CHAR PRIMARY KEY,
  v CHAR,
  CONSTRAINT a INDEX (k, v),
  CONSTRAINT b UNIQUE (v)
);
INSERT INTO t.kv VALUES ('c', 'e'), ('a', 'c'), ('b', 'd');
`); err != nil {
		t.Fatal(err)
	}

	// The first `MaxReservedDescID` (plus 0) are set aside.
	nameKey := sql.MakeNameMetadataKey(sql.MaxReservedDescID+1, "kv")
	gr, err := kvDB.Get(nameKey)
	if err != nil {
		t.Fatal(err)
	}

	if !gr.Exists() {
		t.Fatalf("TableDescriptor %q does not exist", nameKey)
	}

	descKey := sql.MakeDescMetadataKey(sql.ID(gr.ValueInt()))
	desc := sql.TableDescriptor{}
	if err := kvDB.GetProto(descKey, &desc); err != nil {
		t.Fatal(err)
	}

	var tablePrefix []byte
	tablePrefix = append(tablePrefix, keys.TableDataPrefix...)
	tablePrefix = encoding.EncodeUvarint(tablePrefix, uint64(desc.ID))

	tableStartKey := proto.Key(tablePrefix)
	tableEndKey := tableStartKey.PrefixEnd()
	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 12; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	// Insert that will fail after the index `a` is written.
	if _, err := sqlDB.Exec(`INSERT INTO t.kv VALUES ('d', 'd')`); !testutils.IsError(err, "duplicate key value .* violates unique constraint") {
		t.Fatalf("unexpected error %s", err)
	}

	// Verify nothing was written.
	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 12; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}
}

func TestDelete(t *testing.T) {
	defer leaktest.AfterTest(t)
	s, sqlDB, kvDB := setup(t)
	defer cleanup(s, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.kv (
  k CHAR PRIMARY KEY,
  v CHAR,
  CONSTRAINT a UNIQUE (v)
);
INSERT INTO t.kv VALUES ('c', 'e'), ('a', 'c'), ('b', 'd');
`); err != nil {
		t.Fatal(err)
	}

	// The first `MaxReservedDescID` (plus 0) are set aside.
	nameKey := sql.MakeNameMetadataKey(sql.MaxReservedDescID+1, "kv")
	gr, err := kvDB.Get(nameKey)
	if err != nil {
		t.Fatal(err)
	}

	if !gr.Exists() {
		t.Fatalf("TableDescriptor %q does not exist", nameKey)
	}

	descKey := sql.MakeDescMetadataKey(sql.ID(gr.ValueInt()))
	desc := sql.TableDescriptor{}
	if err := kvDB.GetProto(descKey, &desc); err != nil {
		t.Fatal(err)
	}

	var tablePrefix []byte
	tablePrefix = append(tablePrefix, keys.TableDataPrefix...)
	tablePrefix = encoding.EncodeUvarint(tablePrefix, uint64(desc.ID))

	tableStartKey := proto.Key(tablePrefix)
	tableEndKey := tableStartKey.PrefixEnd()
	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 9; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	if _, err := sqlDB.Exec(`DELETE FROM t.kv`); err != nil {
		t.Fatal(err)
	}

	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 0; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}
}

// TestStoreRangeSplitAtTablePrefix verifies a range can be split at
// UserTableDataMin and still gossip the SystemConfig properly.
func TestStoreRangeSplitAtTablePrefix(t *testing.T) {
	defer leaktest.AfterTest(t)
	defer config.TestingDisableTableSplits()()
	store, stopper := createTestStore(t)
	defer stopper.Stop()

	key := keys.MakeNonColumnKey(append([]byte(nil), keys.UserTableDataMin...))
	args := adminSplitArgs(key, key)
	_, err := client.SendWrapped(rg1(store), nil, &args)
	if err != nil {
		t.Fatalf("%q: split unexpected error: %s", key, err)
	}

	desc := &sql.TableDescriptor{}
	descBytes, err := desc.Marshal()
	if err != nil {
		t.Fatal(err)
	}

	// Update SystemConfig to trigger gossip.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemConfigTrigger()
		// We don't care about the values, just the keys.
		k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + 1))
		return txn.Put(k, desc)
	}); err != nil {
		t.Fatal(err)
	}

	successChan := make(chan struct{}, 1)
	store.Gossip().RegisterCallback(gossip.KeySystemConfig, func(_ string, content roachpb.Value) {
		contentBytes, err := content.GetBytes()
		if err != nil {
			t.Fatal(err)
		}
		if bytes.Contains(contentBytes, descBytes) {
			select {
			case successChan <- struct{}{}:
			default:
			}
		}
	})

	select {
	case <-time.After(time.Second):
		t.Errorf("expected a schema gossip containing %q, but did not see one", descBytes)
	case <-successChan:
	}
}

// TestStoreRangeSplitAtTablePrefix verifies a range can be split
// at TableDataPrefix and still gossip the SystemConfig properly.
func TestStoreRangeSplitAtTablePrefix(t *testing.T) {
	defer leaktest.AfterTest(t)
	store, stopper := createTestStore(t)
	defer stopper.Stop()

	key := keys.TableDataPrefix
	args := adminSplitArgs(key, key)
	_, err := client.SendWrapped(rg1(store), nil, &args)
	if err != nil {
		t.Fatalf("%q: split unexpected error: %s", key, err)
	}

	// Update SystemConfig to trigger gossip.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + 1))
		return txn.Put(k, 10)
	}); err != nil {
		t.Fatal(err)
	}
}

func TestSystemDBGossip(t *testing.T) {
	defer leaktest.AfterTest(t)
	s := StartTestServer(t)
	defer s.Stop()

	resultChan := make(chan roachpb.Value)
	var count int32
	db := s.db
	key := sql.MakeDescMetadataKey(keys.MaxReservedDescID)
	valAt := func(i int) *sql.DatabaseDescriptor {
		return &sql.DatabaseDescriptor{Name: "foo", ID: sql.ID(i)}
	}

	// Register a callback for gossip updates.
	s.Gossip().RegisterCallback(gossip.KeySystemConfig, func(_ string, content roachpb.Value) {
		newCount := atomic.AddInt32(&count, 1)
		if newCount != 2 {
			// RegisterCallback calls us right away with the contents,
			// so ignore the very first call.
			// We also only want the first value of all our writes.
			return
		}
		resultChan <- content
	})

	// The span only gets gossiped when it first shows up, or when
	// the EndTransaction trigger is set.

	// Try a plain KV write first.
	if err := db.Put(key, valAt(0)); err != nil {
		t.Fatal(err)
	}

	// Now do it as part of a transaction, but without the trigger set.
	if err := db.Txn(func(txn *client.Txn) error {
		return txn.Put(key, valAt(1))
	}); err != nil {
		t.Fatal(err)
	}

	// This time mark the transaction as having a SystemDB trigger.
	if err := db.Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		return txn.Put(key, valAt(2))
	}); err != nil {
		t.Fatal(err)
	}

	// Wait for the callback.
	var systemConfig config.SystemConfig
	select {
	case content := <-resultChan:
		if err := content.GetProto(&systemConfig); err != nil {
			t.Fatal(err)
		}
	case <-time.After(500 * time.Millisecond):
		t.Fatal("did not receive gossip callback")
	}

	// Now check the gossip callback.
	var val *roachpb.Value
	for _, kv := range systemConfig.Values {
		if bytes.Equal(key, kv.Key) {
			val = &kv.Value
			break
		}
	}
	if val == nil {
		t.Fatal("key not found in gossiped info")
	}

	// Make sure the returned value is valAt(2).
	var got sql.DatabaseDescriptor
	if err := val.GetProto(&got); err != nil {
		t.Fatal(err)
	}
	if got.ID != 2 {
		t.Fatalf("mismatch: expected %+v, got %+v", valAt(2), got)
	}
}

// TestStoreRangeSystemSplits verifies that splits are based on the contents of
// the SystemConfig span.
func TestStoreRangeSystemSplits(t *testing.T) {
	defer leaktest.AfterTest(t)()
	store, stopper, _ := createTestStore(t)
	defer stopper.Stop()

	schema := sql.MakeMetadataSchema()
	initialSystemValues := schema.GetInitialValues()
	var userTableMax int
	// Write the initial sql values to the system DB as well
	// as the equivalent of table descriptors for X user tables.
	// This does two things:
	// - descriptor IDs are used to determine split keys
	// - the write triggers a SystemConfig update and gossip.
	// We should end up with splits at each user table prefix.
	if pErr := store.DB().Txn(func(txn *client.Txn) *roachpb.Error {
		prefix := keys.MakeTablePrefix(keys.DescriptorTableID)
		txn.SetSystemConfigTrigger()
		for i, kv := range initialSystemValues {
			if !bytes.HasPrefix(kv.Key, prefix) {
				continue
			}
			bytes, err := kv.Value.GetBytes()
			if err != nil {
				log.Info(err)
				continue
			}
			if pErr := txn.Put(kv.Key, bytes); pErr != nil {
				return pErr
			}

			descID := keys.MaxReservedDescID + i + 1
			userTableMax = i + 1

			// We don't care about the values, just the keys.
			k := sql.MakeDescMetadataKey(sql.ID(descID))
			if pErr := txn.Put(k, bytes); pErr != nil {
				return pErr
			}
		}
		return nil
	}); pErr != nil {
		t.Fatal(pErr)
	}

	verifySplitsAtTablePrefixes := func(maxTableID int) {
		// We expect splits at each of the user tables, but not at the system
		// tables boundaries.
		expKeys := make([]roachpb.Key, 0, maxTableID+2)

		// We can't simply set numReservedTables to schema.TableCount(), because
		// some system tables are created at cluster bootstrap time. So, before the
		// cluster bootstrap, TableCount() will return a value that's too low.
		numReservedTables := schema.MaxTableID() - keys.MaxSystemConfigDescID
		for i := 1; i <= int(numReservedTables); i++ {
			expKeys = append(expKeys,
				testutils.MakeKey(keys.Meta2Prefix,
					keys.MakeTablePrefix(keys.MaxSystemConfigDescID+uint32(i))),
			)
		}
		for i := 1; i <= maxTableID; i++ {
			expKeys = append(expKeys,
				testutils.MakeKey(keys.Meta2Prefix, keys.MakeTablePrefix(keys.MaxReservedDescID+uint32(i))),
			)
		}
		expKeys = append(expKeys, testutils.MakeKey(keys.Meta2Prefix, roachpb.RKeyMax))

		util.SucceedsSoonDepth(1, t, func() error {
			rows, pErr := store.DB().Scan(keys.Meta2Prefix, keys.MetaMax, 0)
			if pErr != nil {
				return pErr.GoError()
			}
			keys := make([]roachpb.Key, 0, len(expKeys))
			for _, r := range rows {
				keys = append(keys, r.Key)
			}
			if !reflect.DeepEqual(keys, expKeys) {
				return util.Errorf("expected split keys:\n%v\nbut found:\n%v", expKeys, keys)
			}
			return nil
		})
	}

	verifySplitsAtTablePrefixes(userTableMax)

	numTotalValues := keys.MaxSystemConfigDescID + 5

	// Write another, disjoint descriptor for a user table.
	if pErr := store.DB().Txn(func(txn *client.Txn) *roachpb.Error {
		txn.SetSystemConfigTrigger()
		// This time, only write the last table descriptor. Splits
		// still occur for every intervening ID.
		// We don't care about the values, just the keys.
		k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + numTotalValues))
		return txn.Put(k, &sql.TableDescriptor{})
	}); pErr != nil {
		t.Fatal(pErr)
	}

//.........這裏部分代碼省略.........

func TestCommandsWithPendingMutations(t *testing.T) {
	defer leaktest.AfterTest(t)
	// The descriptor changes made must have an immediate effect
	// so disable leases on tables.
	defer csql.TestDisableTableLeases()()
	// Disable external processing of mutations.
	defer csql.TestDisableAsyncSchemaChangeExec()()
	server, sqlDB, kvDB := setup(t)
	defer cleanup(server, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.test (a CHAR PRIMARY KEY, b CHAR, c CHAR, INDEX foo (c));
`); err != nil {
		t.Fatal(err)
	}

	// Read table descriptor
	nameKey := csql.MakeNameMetadataKey(keys.MaxReservedDescID+1, "test")
	gr, err := kvDB.Get(nameKey)
	if err != nil {
		t.Fatal(err)
	}
	if !gr.Exists() {
		t.Fatalf("Name entry %q does not exist", nameKey)
	}
	descKey := csql.MakeDescMetadataKey(csql.ID(gr.ValueInt()))
	desc := &csql.Descriptor{}
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}

	mt := mutationTest{
		T:       t,
		kvDB:    kvDB,
		sqlDB:   sqlDB,
		descKey: descKey,
		desc:    desc,
	}

	// Test CREATE INDEX in the presence of mutations.

	// Add index DROP mutation "foo""
	mt.writeIndexMutation("foo", csql.DescriptorMutation{Direction: csql.DescriptorMutation_DROP})
	if _, err := sqlDB.Exec(`CREATE INDEX foo ON t.test (c)`); !testutils.IsError(err, `index "foo" being dropped, try again later`) {
		t.Fatal(err)
	}
	// Make "foo" live.
	mt.makeMutationsActive()

	// "foo" is being added.
	mt.writeIndexMutation("foo", csql.DescriptorMutation{Direction: csql.DescriptorMutation_ADD})
	if _, err := sqlDB.Exec(`CREATE INDEX foo ON t.test (c)`); !testutils.IsError(err, `duplicate index name: "foo"`) {
		t.Fatal(err)
	}
	// Make "foo" live.
	mt.makeMutationsActive()
	// Add column DROP mutation "b"
	mt.writeColumnMutation("b", csql.DescriptorMutation{Direction: csql.DescriptorMutation_DROP})
	if _, err := sqlDB.Exec(`CREATE INDEX bar ON t.test (b)`); !testutils.IsError(err, `index "bar" contains unknown column "b"`) {
		t.Fatal(err)
	}
	// Make "b" live.
	mt.makeMutationsActive()
	// "b" is being added.
	mt.writeColumnMutation("b", csql.DescriptorMutation{Direction: csql.DescriptorMutation_ADD})
	// An index referencing a column mutation that is being added
	// is allowed to be added.
	if _, err := sqlDB.Exec(`CREATE INDEX bar ON t.test (b)`); err != nil {
		t.Fatal(err)
	}
	// Make "b" live.
	mt.makeMutationsActive()

	// Test DROP INDEX in the presence of mutations.

	// Add index DROP mutation "foo""
	mt.writeIndexMutation("foo", csql.DescriptorMutation{Direction: csql.DescriptorMutation_DROP})
	// Noop.
	if _, err := sqlDB.Exec(`DROP INDEX [email protected]`); err != nil {
		t.Fatal(err)
	}
	// Make "foo" live.
	mt.makeMutationsActive()
	// "foo" is being added.
	mt.writeIndexMutation("foo", csql.DescriptorMutation{Direction: csql.DescriptorMutation_ADD})
	if _, err := sqlDB.Exec(`DROP INDEX [email protected]`); !testutils.IsError(err, `index "foo" in the middle of being added, try again later`) {
		t.Fatal(err)
	}
	// Make "foo" live.
	mt.makeMutationsActive()
	// Test ALTER TABLE ADD/DROP column in the presence of mutations.

	// Add column DROP mutation "b"
	mt.writeColumnMutation("b", csql.DescriptorMutation{Direction: csql.DescriptorMutation_DROP})
	if _, err := sqlDB.Exec(`ALTER TABLE t.test ADD b CHAR`); !testutils.IsError(err, `column "b" being dropped, try again later`) {
		t.Fatal(err)
	}
	// Noop.
	if _, err := sqlDB.Exec(`ALTER TABLE t.test DROP b`); err != nil {
//.........這裏部分代碼省略.........

// TestStoreRangeSystemSplits verifies that splits are based on the
// contents of the SystemDB span.
func TestStoreRangeSystemSplits(t *testing.T) {
	defer leaktest.AfterTest(t)
	store, stopper := createTestStore(t)
	defer stopper.Stop()

	// Write the initial sql values to the system DB as well
	// as the equivalent of table descriptors for X user tables.
	// This does two things:
	// - descriptor IDs are used to determine split keys
	// - the write triggers a SystemConfig update and gossip.
	// We should end up with splits at each user table prefix.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		for _, kv := range sql.GetInitialSystemValues() {
			if err := txn.Put(kv.Key, kv.Value.GetRawBytes()); err != nil {
				return err
			}
		}
		for i := 1; i <= 5; i++ {
			// We don't care about the values, just the keys.
			k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + i))
			v, err := txn.Get(k)
			if err != nil {
				return err
			}
			if err := txn.Put(k, v.ValueBytes()); err != nil {
				return err
			}
		}
		return nil
	}); err != nil {
		t.Fatal(err)
	}

	expKeys := []roachpb.Key{}
	for i := 1; i <= 5; i++ {
		expKeys = append(expKeys, keys.MakeKey(keys.Meta2Prefix,
			keys.MakeTablePrefix(uint32(keys.MaxReservedDescID+i))))
	}
	expKeys = append(expKeys, keys.MakeKey(keys.Meta2Prefix, roachpb.RKeyMax))

	if err := util.IsTrueWithin(func() bool {
		rows, err := store.DB().Scan(keys.Meta2Prefix, keys.MetaMax, 0)
		if err != nil {
			t.Fatalf("failed to scan meta2 keys: %s", err)
		}
		var keys []roachpb.Key
		for _, r := range rows {
			keys = append(keys, r.Key)
		}
		return reflect.DeepEqual(keys, expKeys)
	}, 5*time.Second); err != nil {
		t.Errorf("expected splits not found: %s", err)
	}

	// Write more descriptors for user tables.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		// This time, only write the last table descriptor. Splits
		// still occur for every ID.
		// We don't care about the values, just the keys.
		k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + 10))
		v, err := txn.Get(k)
		if err != nil {
			return err
		}
		return txn.Put(k, v.ValueBytes())
	}); err != nil {
		t.Fatal(err)
	}

	expKeys = []roachpb.Key{}
	for i := 1; i <= 10; i++ {
		expKeys = append(expKeys, keys.MakeKey(keys.Meta2Prefix,
			keys.MakeTablePrefix(uint32(keys.MaxReservedDescID+i))))
	}
	expKeys = append(expKeys, keys.MakeKey(keys.Meta2Prefix, roachpb.RKeyMax))

	if err := util.IsTrueWithin(func() bool {
		rows, err := store.DB().Scan(keys.Meta2Prefix, keys.MetaMax, 0)
		if err != nil {
			t.Fatalf("failed to scan meta2 keys: %s", err)
		}
		var keys []roachpb.Key
		for _, r := range rows {
			keys = append(keys, r.Key)
		}
		return reflect.DeepEqual(keys, expKeys)
	}, 5*time.Second); err != nil {
		t.Errorf("expected splits not found: %s", err)
	}
}

// TestStoreRangeSystemSplits verifies that splits are based on the
// contents of the SystemDB span.
func TestStoreRangeSystemSplits(t *testing.T) {
	defer leaktest.AfterTest(t)
	store, stopper := createTestStore(t)
	defer stopper.Stop()

	initialSystemValues := sql.MakeMetadataSchema().GetInitialValues()
	numInitialValues := len(initialSystemValues)
	// Write the initial sql values to the system DB as well
	// as the equivalent of table descriptors for X user tables.
	// This does two things:
	// - descriptor IDs are used to determine split keys
	// - the write triggers a SystemConfig update and gossip.
	// We should end up with splits at each user table prefix.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		for i, kv := range initialSystemValues {
			bytes, err := kv.Value.GetBytes()
			if err != nil {
				log.Info(err)
				continue
			}
			if err := txn.Put(kv.Key, bytes); err != nil {
				return err
			}

			descID := keys.MaxReservedDescID + i + 1

			// We don't care about the values, just the keys.
			k := sql.MakeDescMetadataKey(sql.ID(descID))
			if err := txn.Put(k, bytes); err != nil {
				return err
			}
		}
		return nil
	}); err != nil {
		t.Fatal(err)
	}

	verifySplitsAtTablePrefixes := func(maxTableID int) {
		// We expect splits at each of the user tables, but not at the system
		// tables boundaries.
		expKeys := make([]roachpb.Key, 0, maxTableID+1)
		for i := 1; i <= maxTableID; i++ {
			expKeys = append(expKeys,
				keys.MakeKey(keys.Meta2Prefix, keys.MakeTablePrefix(keys.MaxReservedDescID+uint32(i))),
			)
		}
		expKeys = append(expKeys, keys.MakeKey(keys.Meta2Prefix, roachpb.RKeyMax))

		util.SucceedsWithinDepth(1, t, 5*time.Second, func() error {
			rows, err := store.DB().Scan(keys.Meta2Prefix, keys.MetaMax, 0)
			if err != nil {
				return err
			}
			keys := make([]roachpb.Key, 0, len(expKeys))
			for _, r := range rows {
				keys = append(keys, r.Key)
			}
			if !reflect.DeepEqual(keys, expKeys) {
				return util.Errorf("expected split keys:\n%v\nbut found:\n%v", expKeys, keys)
			}
			return nil
		})
	}

	verifySplitsAtTablePrefixes(len(initialSystemValues))

	numTotalValues := numInitialValues + 5

	// Write another, disjoint descriptor for a user table.
	if err := store.DB().Txn(func(txn *client.Txn) error {
		txn.SetSystemDBTrigger()
		// This time, only write the last table descriptor. Splits
		// still occur for every intervening ID.
		// We don't care about the values, just the keys.
		k := sql.MakeDescMetadataKey(sql.ID(keys.MaxReservedDescID + numTotalValues))
		return txn.Put(k, &sql.TableDescriptor{})
	}); err != nil {
		t.Fatal(err)
	}

	verifySplitsAtTablePrefixes(numTotalValues)
}

// Test schema change backfills are not affected by various operations
// that run simultaneously.
func TestRaceWithBackfill(t *testing.T) {
	defer leaktest.AfterTest(t)()
	server, sqlDB, kvDB := setup(t)
	defer cleanup(server, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.test (k INT PRIMARY KEY, v INT);
`); err != nil {
		t.Fatal(err)
	}

	// Bulk insert.
	max_value := 2000
	insert := fmt.Sprintf(`INSERT INTO t.test VALUES (%d, %d)`, 0, max_value)
	for i := 1; i <= max_value; i++ {
		insert += fmt.Sprintf(` ,(%d, %d)`, i, max_value-i)
	}
	if _, err := sqlDB.Exec(insert); err != nil {
		t.Fatal(err)
	}

	// Read table descriptor for version.
	nameKey := csql.MakeNameMetadataKey(keys.MaxReservedDescID+1, "test")
	gr, pErr := kvDB.Get(nameKey)
	if pErr != nil {
		t.Fatal(pErr)
	}
	if !gr.Exists() {
		t.Fatalf("Name entry %q does not exist", nameKey)
	}
	descKey := csql.MakeDescMetadataKey(csql.ID(gr.ValueInt()))
	desc := &csql.Descriptor{}
	if pErr := kvDB.GetProto(descKey, desc); pErr != nil {
		t.Fatal(pErr)
	}
	version := desc.GetTable().Version

	// Run the schema changes in a separate goroutine.
	var wg sync.WaitGroup
	wg.Add(1)
	go func() {
		start := timeutil.Now()
		// Start schema change that eventually runs a number of backfills.
		if _, err := sqlDB.Exec(`
BEGIN;
ALTER TABLE t.test ADD COLUMN x DECIMAL DEFAULT (DECIMAL '1.4');
CREATE UNIQUE INDEX foo ON t.test (v);
END;
`); err != nil {
			t.Error(err)
		}
		t.Logf("schema changes took %v", time.Since(start))
		wg.Done()
	}()

	// Wait until the backfills for the schema changes above have
	// started.
	util.SucceedsSoon(t, func() error {
		if pErr := kvDB.GetProto(descKey, desc); pErr != nil {
			t.Fatal(pErr)
		}
		if desc.GetTable().Version == version+2 {
			// Version upgrade has happened, backfills can proceed.
			return nil
		}
		return errors.New("version not updated")
	})

	// TODO(vivek): uncomment these inserts when #5817 is fixed.
	// Insert some new rows in the table while the backfills are running.
	//num_values := 5
	//for i := 0; i < num_values; i++ {
	//	t.Logf("inserting a new value into the table")
	//	if _, err := sqlDB.Exec(`INSERT INTO t.test VALUES($1, $2)`, max_value+i+1, max_value+i+1); err != nil {
	//		t.Fatal(err)
	//	}
	//}

	// Renaming an index in the middle of the backfills will not affect
	// the backfills because the above schema changes have the schema change
	// lease on the table. All future schema changes have to wait in line for
	// the lease.
	if _, err := sqlDB.Exec(`
ALTER INDEX [email protected] RENAME TO bar;
`); err != nil {
		t.Fatal(err)
	}

	// Wait until schema changes have completed.
	wg.Wait()

	// Verify that the index over v is consistent.
	rows, err := sqlDB.Query(`SELECT v from [email protected]`)
	if err != nil {
		t.Fatal(err)
	}

//.........這裏部分代碼省略.........

func TestDropDatabase(t *testing.T) {
	defer leaktest.AfterTest(t)
	s, sqlDB, kvDB := setup(t)
	defer cleanup(s, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.kv (k CHAR PRIMARY KEY, v CHAR);
INSERT INTO t.kv VALUES ('c', 'e'), ('a', 'c'), ('b', 'd');
`); err != nil {
		t.Fatal(err)
	}

	dbNameKey := sql.MakeNameMetadataKey(sql.RootNamespaceID, "t")
	r, err := kvDB.Get(dbNameKey)
	if err != nil {
		t.Fatal(err)
	}
	if !r.Exists() {
		t.Fatalf(`database "t" does not exist`)
	}
	dbDescKey := sql.MakeDescMetadataKey(sql.ID(r.ValueInt()))
	dbDesc := sql.DatabaseDescriptor{}
	if err := kvDB.GetProto(dbDescKey, &dbDesc); err != nil {
		t.Fatal(err)
	}

	tbNameKey := sql.MakeNameMetadataKey(dbDesc.ID, "kv")
	gr, err := kvDB.Get(tbNameKey)
	if err != nil {
		t.Fatal(err)
	}
	if !gr.Exists() {
		t.Fatalf(`table "kv" does not exist`)
	}
	tbDescKey := sql.MakeDescMetadataKey(sql.ID(gr.ValueInt()))
	tbDesc := sql.TableDescriptor{}
	if err := kvDB.GetProto(tbDescKey, &tbDesc); err != nil {
		t.Fatal(err)
	}

	var tablePrefix []byte
	tablePrefix = append(tablePrefix, keys.TableDataPrefix...)
	tablePrefix = encoding.EncodeUvarint(tablePrefix, uint64(tbDesc.ID))

	tableStartKey := proto.Key(tablePrefix)
	tableEndKey := tableStartKey.PrefixEnd()
	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 6; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	if _, err := sqlDB.Exec(`DROP DATABASE t`); err != nil {
		t.Fatal(err)
	}

	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 0; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	if gr, err := kvDB.Get(tbDescKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("table descriptor still exists after database is dropped")
	}

	if gr, err := kvDB.Get(tbNameKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("table descriptor key still exists after database is dropped")
	}

	if gr, err := kvDB.Get(dbDescKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("database descriptor still exists after database is dropped")
	}

	if gr, err := kvDB.Get(dbNameKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("database descriptor key still exists after database is dropped")
	}
}

// TestRenameTable tests the table descriptor changes during
// a rename operation.
func TestRenameTable(t *testing.T) {
	defer leaktest.AfterTest(t)
	defer config.TestingDisableTableSplits()()
	s, sqlDB, kvDB := setup(t)
	defer cleanup(s, sqlDB)

	counter := int64(keys.MaxReservedDescID + 1)

	// Table creation should fail, and nothing should have been written.
	oldDBID := sql.ID(counter)
	if _, err := sqlDB.Exec(`CREATE DATABASE test`); err != nil {
		t.Fatal(err)
	}
	counter++

	// Create table in 'test'.
	tableCounter := counter
	oldName := "foo"
	if _, err := sqlDB.Exec(`CREATE TABLE test.foo (k INT PRIMARY KEY, v int)`); err != nil {
		t.Fatal(err)
	}
	counter++

	// Check the table descriptor.
	desc := &sql.Descriptor{}
	tableDescKey := sql.MakeDescMetadataKey(sql.ID(tableCounter))
	if err := kvDB.GetProto(tableDescKey, desc); err != nil {
		t.Fatal(err)
	}
	tableDesc := desc.GetTable()
	if tableDesc.Name != oldName {
		t.Fatalf("Wrong table name, expected %s, got: %+v", oldName, tableDesc)
	}
	if tableDesc.ParentID != oldDBID {
		t.Fatalf("Wrong parent ID on table, expected %d, got: %+v", oldDBID, tableDesc)
	}

	// Create database test2.
	newDBID := sql.ID(counter)
	if _, err := sqlDB.Exec(`CREATE DATABASE test2`); err != nil {
		t.Fatal(err)
	}
	counter++

	// Move table to test2 and change its name as well.
	newName := "bar"
	if _, err := sqlDB.Exec(`ALTER TABLE test.foo RENAME TO test2.bar`); err != nil {
		t.Fatal(err)
	}

	// Check the table descriptor again.
	if err := kvDB.GetProto(tableDescKey, desc); err != nil {
		t.Fatal(err)
	}
	tableDesc = desc.GetTable()
	if tableDesc.Name != newName {
		t.Fatalf("Wrong table name, expected %s, got: %+v", newName, tableDesc)
	}
	if tableDesc.ParentID != newDBID {
		t.Fatalf("Wrong parent ID on table, expected %d, got: %+v", newDBID, tableDesc)
	}
}

func TestSchemaChangeProcess(t *testing.T) {
	defer leaktest.AfterTest(t)
	// The descriptor changes made must have an immediate effect
	// so disable leases on tables.
	defer csql.TestDisableTableLeases()()
	// Disable external processing of mutations.
	defer csql.TestDisableAsyncSchemaChangeExec()()
	server, sqlDB, kvDB := setup(t)
	defer cleanup(server, sqlDB)
	var id = csql.ID(keys.MaxReservedDescID + 2)
	var node = roachpb.NodeID(2)
	db := server.DB()
	leaseMgr := csql.NewLeaseManager(0, *db, hlc.NewClock(hlc.UnixNano))
	changer := csql.NewSchemaChangerForTesting(id, 0, node, *db, leaseMgr)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.test (k CHAR PRIMARY KEY, v CHAR, INDEX foo(v));
INSERT INTO t.test VALUES ('a', 'b'), ('c', 'd');
`); err != nil {
		t.Fatal(err)
	}

	// Read table descriptor for version.
	nameKey := csql.MakeNameMetadataKey(keys.MaxReservedDescID+1, "test")
	gr, err := kvDB.Get(nameKey)
	if err != nil {
		t.Fatal(err)
	}
	if !gr.Exists() {
		t.Fatalf("Name entry %q does not exist", nameKey)
	}
	descKey := csql.MakeDescMetadataKey(csql.ID(gr.ValueInt()))
	desc := &csql.Descriptor{}

	// Check that MaybeIncrementVersion doesn't increment the version
	// when the up_version bit is not set.
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
	expectedVersion := desc.GetTable().Version

	if err := changer.MaybeIncrementVersion(); err != nil {
		t.Fatal(err)
	}
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
	newVersion := desc.GetTable().Version
	if newVersion != expectedVersion {
		t.Fatalf("bad version; e = %d, v = %d", expectedVersion, newVersion)
	}
	isDone, err := changer.IsDone()
	if err != nil {
		t.Fatal(err)
	}
	if !isDone {
		t.Fatalf("table expected to not have an outstanding schema change: %v", desc.GetTable())
	}

	// Check that MaybeIncrementVersion increments the version
	// correctly.
	expectedVersion++
	desc.GetTable().UpVersion = true
	if err := kvDB.Put(descKey, desc); err != nil {
		t.Fatal(err)
	}
	isDone, err = changer.IsDone()
	if err != nil {
		t.Fatal(err)
	}
	if isDone {
		t.Fatalf("table expected to have an outstanding schema change: %v", desc.GetTable())
	}
	if err := changer.MaybeIncrementVersion(); err != nil {
		t.Fatal(err)
	}
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
	newVersion = desc.GetTable().Version
	if newVersion != expectedVersion {
		t.Fatalf("bad version; e = %d, v = %d", expectedVersion, newVersion)
	}
	isDone, err = changer.IsDone()
	if err != nil {
		t.Fatal(err)
	}
	if !isDone {
		t.Fatalf("table expected to not have an outstanding schema change: %v", desc.GetTable())
	}

	// Check that RunStateMachineBeforeBackfill doesn't do anything
	// if there are no mutations queued.
	if err := changer.RunStateMachineBeforeBackfill(); err != nil {
		t.Fatal(err)
	}
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
//.........這裏部分代碼省略.........

func TestAsyncSchemaChanger(t *testing.T) {
	defer leaktest.AfterTest(t)
	// Disable synchronous schema change execution so
	// the asynchronous schema changer executes all
	// schema changes.
	defer csql.TestDisableSyncSchemaChangeExec()()
	// The descriptor changes made must have an immediate effect
	// so disable leases on tables.
	defer csql.TestDisableTableLeases()()
	server, sqlDB, kvDB := setup(t)
	defer cleanup(server, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.test (k CHAR PRIMARY KEY, v CHAR);
INSERT INTO t.test VALUES ('a', 'b'), ('c', 'd');
`); err != nil {
		t.Fatal(err)
	}

	// Read table descriptor for version.
	nameKey := csql.MakeNameMetadataKey(keys.MaxReservedDescID+1, "test")
	gr, err := kvDB.Get(nameKey)
	if err != nil {
		t.Fatal(err)
	}
	if !gr.Exists() {
		t.Fatalf("Name entry %q does not exist", nameKey)
	}
	descKey := csql.MakeDescMetadataKey(csql.ID(gr.ValueInt()))
	desc := &csql.Descriptor{}
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
	// A long running schema change operation runs through
	// a state machine that increments the version by 3.
	expectedVersion := desc.GetTable().Version + 3

	// Run some schema change
	if _, err := sqlDB.Exec(`
CREATE INDEX foo ON t.test (v)
`); err != nil {
		t.Fatal(err)
	}

	retryOpts := retry.Options{
		InitialBackoff: 20 * time.Millisecond,
		MaxBackoff:     200 * time.Millisecond,
		Multiplier:     2,
	}

	// Wait until index is created.
	for r := retry.Start(retryOpts); r.Next(); {
		if err := kvDB.GetProto(descKey, desc); err != nil {
			t.Fatal(err)
		}
		if len(desc.GetTable().Indexes) == 1 {
			break
		}
	}

	// Ensure that the indexes have been created.
	mTest := mutationTest{
		T:       t,
		kvDB:    kvDB,
		sqlDB:   sqlDB,
		descKey: descKey,
		desc:    desc,
	}
	indexQuery := `SELECT * FROM [email protected]`
	_ = mTest.checkQueryResponse(indexQuery, [][]string{{"b"}, {"d"}})

	// Ensure that the version has been incremented.
	if err := kvDB.GetProto(descKey, desc); err != nil {
		t.Fatal(err)
	}
	newVersion := desc.GetTable().Version
	if newVersion != expectedVersion {
		t.Fatalf("bad version; e = %d, v = %d", expectedVersion, newVersion)
	}

	// Apply a schema change that only sets the UpVersion bit.
	expectedVersion = newVersion + 1

	if _, err := sqlDB.Exec(`
ALTER INDEX [email protected] RENAME TO ufo
`); err != nil {
		t.Fatal(err)
	}

	for r := retry.Start(retryOpts); r.Next(); {
		// Ensure that the version gets incremented.
		if err := kvDB.GetProto(descKey, desc); err != nil {
			t.Fatal(err)
		}
		name := desc.GetTable().Indexes[0].Name
		if name != "ufo" {
			t.Fatalf("bad index name %s", name)
		}
		newVersion = desc.GetTable().Version
//.........這裏部分代碼省略.........

func TestDropDatabase(t *testing.T) {
	defer leaktest.AfterTest(t)()
	s, sqlDB, kvDB := setup(t)
	defer cleanup(s, sqlDB)

	if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.kv (k CHAR PRIMARY KEY, v CHAR);
INSERT INTO t.kv VALUES ('c', 'e'), ('a', 'c'), ('b', 'd');
`); err != nil {
		t.Fatal(err)
	}

	dbNameKey := sql.MakeNameMetadataKey(keys.RootNamespaceID, "t")
	r, pErr := kvDB.Get(dbNameKey)
	if pErr != nil {
		t.Fatal(pErr)
	}
	if !r.Exists() {
		t.Fatalf(`database "t" does not exist`)
	}
	dbDescKey := sql.MakeDescMetadataKey(sql.ID(r.ValueInt()))
	desc := &sql.Descriptor{}
	if pErr := kvDB.GetProto(dbDescKey, desc); pErr != nil {
		t.Fatal(pErr)
	}
	dbDesc := desc.GetDatabase()

	tbNameKey := sql.MakeNameMetadataKey(dbDesc.ID, "kv")
	gr, pErr := kvDB.Get(tbNameKey)
	if pErr != nil {
		t.Fatal(pErr)
	}
	if !gr.Exists() {
		t.Fatalf(`table "kv" does not exist`)
	}
	tbDescKey := sql.MakeDescMetadataKey(sql.ID(gr.ValueInt()))
	if pErr := kvDB.GetProto(tbDescKey, desc); pErr != nil {
		t.Fatal(pErr)
	}
	tbDesc := desc.GetTable()

	// Add a zone config for both the table and database.
	cfg := config.DefaultZoneConfig()
	buf, err := proto.Marshal(&cfg)
	if err != nil {
		t.Fatal(err)
	}
	if _, err := sqlDB.Exec(`INSERT INTO system.zones VALUES ($1, $2)`, tbDesc.ID, buf); err != nil {
		t.Fatal(err)
	}
	if _, err := sqlDB.Exec(`INSERT INTO system.zones VALUES ($1, $2)`, dbDesc.ID, buf); err != nil {
		t.Fatal(err)
	}

	tbZoneKey := sql.MakeZoneKey(tbDesc.ID)
	dbZoneKey := sql.MakeZoneKey(dbDesc.ID)
	if gr, err := kvDB.Get(tbZoneKey); err != nil {
		t.Fatal(err)
	} else if !gr.Exists() {
		t.Fatalf("table zone config entry not found")
	}
	if gr, err := kvDB.Get(dbZoneKey); err != nil {
		t.Fatal(err)
	} else if !gr.Exists() {
		t.Fatalf("database zone config entry not found")
	}

	tablePrefix := keys.MakeTablePrefix(uint32(tbDesc.ID))
	tableStartKey := roachpb.Key(tablePrefix)
	tableEndKey := tableStartKey.PrefixEnd()
	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 6; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	if _, err := sqlDB.Exec(`DROP DATABASE t`); err != nil {
		t.Fatal(err)
	}

	if kvs, err := kvDB.Scan(tableStartKey, tableEndKey, 0); err != nil {
		t.Fatal(err)
	} else if l := 0; len(kvs) != l {
		t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
	}

	if gr, err := kvDB.Get(tbDescKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("table descriptor still exists after database is dropped")
	}

	if gr, err := kvDB.Get(tbNameKey); err != nil {
		t.Fatal(err)
	} else if gr.Exists() {
		t.Fatalf("table descriptor key still exists after database is dropped")
	}

	if gr, err := kvDB.Get(dbDescKey); err != nil {
//.........這裏部分代碼省略.........