// getCachedDatabaseDesc looks up the database descriptor given its name in the
// descriptor cache.
func (p *planner) getCachedDatabaseDesc(name string) (*sqlbase.DatabaseDescriptor, error) {
if name == sqlbase.SystemDB.Name {
return &sqlbase.SystemDB, nil
}
nameKey := databaseKey{name}
nameVal := p.systemConfig.GetValue(nameKey.Key())
if nameVal == nil {
return nil, fmt.Errorf("database %q does not exist in system cache", name)
}
id, err := nameVal.GetInt()
if err != nil {
return nil, err
}
descKey := sqlbase.MakeDescMetadataKey(sqlbase.ID(id))
descVal := p.systemConfig.GetValue(descKey)
if descVal == nil {
return nil, fmt.Errorf("database %q has name entry, but no descriptor in system cache", name)
}
desc := &sqlbase.Descriptor{}
if err := descVal.GetProto(desc); err != nil {
return nil, err
}
database := desc.GetDatabase()
if database == nil {
return nil, util.Errorf("%q is not a database", name)
}
return database, database.Validate()
}
// Convert all the mutations into live descriptors for the table
// and write the updated table descriptor to the DB.
func (mt mutationTest) makeMutationsActive() {
// Remove mutation to check real values in DB using SQL
if mt.tableDesc.Mutations == nil || len(mt.tableDesc.Mutations) == 0 {
mt.Fatal("No mutations to make active")
}
for _, m := range mt.tableDesc.Mutations {
if col := m.GetColumn(); col != nil {
mt.tableDesc.Columns = append(mt.tableDesc.Columns, *col)
} else if index := m.GetIndex(); index != nil {
mt.tableDesc.Indexes = append(mt.tableDesc.Indexes, *index)
} else {
mt.Fatalf("no descriptor in mutation: %v", m)
}
}
mt.tableDesc.Mutations = nil
if err := mt.tableDesc.Validate(); err != nil {
mt.Fatal(err)
}
if err := mt.kvDB.Put(
sqlbase.MakeDescMetadataKey(mt.tableDesc.ID),
sqlbase.WrapDescriptor(mt.tableDesc),
); err != nil {
mt.Fatal(err)
}
}
// AcquireLease acquires a schema change lease on the table if
// an unexpired lease doesn't exist. It returns the lease.
func (sc *SchemaChanger) AcquireLease() (sqlbase.TableDescriptor_SchemaChangeLease, error) {
var lease sqlbase.TableDescriptor_SchemaChangeLease
err := sc.db.Txn(func(txn *client.Txn) error {
txn.SetSystemConfigTrigger()
tableDesc, err := getTableDescFromID(txn, sc.tableID)
if err != nil {
return err
}
// A second to deal with the time uncertainty across nodes.
// It is perfectly valid for two or more goroutines to hold a valid
// lease and execute a schema change in parallel, because schema
// changes are executed using transactions that run sequentially.
// This just reduces the probability of a write collision.
expirationTimeUncertainty := time.Second
if tableDesc.Lease != nil {
if time.Unix(0, tableDesc.Lease.ExpirationTime).Add(expirationTimeUncertainty).After(timeutil.Now()) {
return errExistingSchemaChangeLease
}
log.Infof("Overriding existing expired lease %v", tableDesc.Lease)
}
lease = sc.createSchemaChangeLease()
tableDesc.Lease = &lease
return txn.Put(sqlbase.MakeDescMetadataKey(tableDesc.ID), sqlbase.WrapDescriptor(tableDesc))
})
return lease, err
}
func (p *planner) createDescriptorWithID(
idKey roachpb.Key, id sqlbase.ID, descriptor sqlbase.DescriptorProto,
) (bool, error) {
descriptor.SetID(id)
// TODO(pmattis): The error currently returned below is likely going to be
// difficult to interpret.
//
// TODO(pmattis): Need to handle if-not-exists here as well.
//
// TODO(pmattis): This is writing the namespace and descriptor table entries,
// but not going through the normal INSERT logic and not performing a precise
// mimicry. In particular, we're only writing a single key per table, while
// perfect mimicry would involve writing a sentinel key for each row as well.
descKey := sqlbase.MakeDescMetadataKey(descriptor.GetID())
b := &client.Batch{}
descID := descriptor.GetID()
descDesc := sqlbase.WrapDescriptor(descriptor)
if log.V(2) {
log.Infof(p.ctx(), "CPut %s -> %d", idKey, descID)
log.Infof(p.ctx(), "CPut %s -> %s", descKey, descDesc)
}
b.CPut(idKey, descID, nil)
b.CPut(descKey, descDesc, nil)
p.setTestingVerifyMetadata(func(systemConfig config.SystemConfig) error {
if err := expectDescriptorID(systemConfig, idKey, descID); err != nil {
return err
}
return expectDescriptor(systemConfig, descKey, descDesc)
})
return true, p.txn.Run(b)
}
// writeTableDesc implements the SchemaAccessor interface.
func (p *planner) writeTableDesc(tableDesc *sqlbase.TableDescriptor) error {
if isVirtualDescriptor(tableDesc) {
panic(fmt.Sprintf("Virtual Descriptors cannot be stored, found: %v", tableDesc))
}
return p.txn.Put(sqlbase.MakeDescMetadataKey(tableDesc.GetID()),
sqlbase.WrapDescriptor(tableDesc))
}
// writeMutation writes the mutation to the table descriptor. If the
// State or the Direction is undefined, these values are populated via
// picking random values before the mutation is written.
func (mt mutationTest) writeMutation(m sqlbase.DescriptorMutation) {
if m.Direction == sqlbase.DescriptorMutation_NONE {
// randomly pick ADD/DROP mutation if this is the first mutation, or
// pick the direction already chosen for the first mutation.
if len(mt.tableDesc.Mutations) > 0 {
m.Direction = mt.tableDesc.Mutations[0].Direction
} else {
m.Direction = sqlbase.DescriptorMutation_DROP
if rand.Intn(2) == 0 {
m.Direction = sqlbase.DescriptorMutation_ADD
}
}
}
if m.State == sqlbase.DescriptorMutation_UNKNOWN {
// randomly pick DELETE_ONLY/WRITE_ONLY state.
r := rand.Intn(2)
if r == 0 {
m.State = sqlbase.DescriptorMutation_DELETE_ONLY
} else {
m.State = sqlbase.DescriptorMutation_WRITE_ONLY
}
}
mt.tableDesc.Mutations = append(mt.tableDesc.Mutations, m)
if err := mt.tableDesc.Validate(); err != nil {
mt.Fatal(err)
}
if err := mt.kvDB.Put(
sqlbase.MakeDescMetadataKey(mt.tableDesc.ID),
sqlbase.WrapDescriptor(mt.tableDesc),
); err != nil {
mt.Fatal(err)
}
}
// waitForOneVersion returns once there are no unexpired leases on the
// previous version of the table descriptor. It returns the current version.
// After returning there can only be versions of the descriptor >= to the
// returned version. Lease acquisition (see acquire()) maintains the
// invariant that no new leases for desc.Version-1 will be granted once
// desc.Version exists.
func (s LeaseStore) waitForOneVersion(tableID sqlbase.ID, retryOpts retry.Options) (
sqlbase.DescriptorVersion, error,
) {
desc := &sqlbase.Descriptor{}
descKey := sqlbase.MakeDescMetadataKey(tableID)
var tableDesc *sqlbase.TableDescriptor
for r := retry.Start(retryOpts); r.Next(); {
// Get the current version of the table descriptor non-transactionally.
//
// TODO(pmattis): Do an inconsistent read here?
if err := s.db.GetProto(descKey, desc); err != nil {
return 0, err
}
tableDesc = desc.GetTable()
if tableDesc == nil {
return 0, errors.Errorf("ID %d is not a table", tableID)
}
// Check to see if there are any leases that still exist on the previous
// version of the descriptor.
now := s.clock.Now()
count, err := s.countLeases(tableDesc.ID, tableDesc.Version-1, now.GoTime())
if err != nil {
return 0, err
}
if count == 0 {
break
}
log.Infof(context.TODO(), "publish (count leases): descID=%d name=%s version=%d count=%d",
tableDesc.ID, tableDesc.Name, tableDesc.Version-1, count)
}
return tableDesc.Version, nil
}
// GetZoneConfig returns the zone config for the object with 'id'.
func GetZoneConfig(cfg config.SystemConfig, id uint32) (config.ZoneConfig, bool, error) {
// Look in the zones table.
if zoneVal := cfg.GetValue(sqlbase.MakeZoneKey(sqlbase.ID(id))); zoneVal != nil {
var zone config.ZoneConfig
// We're done.
return zone, true, zoneVal.GetProto(&zone)
}
// No zone config for this ID. We need to figure out if it's a database
// or table. Lookup its descriptor.
if descVal := cfg.GetValue(sqlbase.MakeDescMetadataKey(sqlbase.ID(id))); descVal != nil {
// Determine whether this is a database or table.
var desc sqlbase.Descriptor
if err := descVal.GetProto(&desc); err != nil {
return config.ZoneConfig{}, false, err
}
if tableDesc := desc.GetTable(); tableDesc != nil {
// This is a table descriptor. Lookup its parent database zone config.
return GetZoneConfig(cfg, uint32(tableDesc.ParentID))
}
}
// Retrieve the default zone config, but only as long as that wasn't the ID
// we were trying to retrieve (avoid infinite recursion).
if id != keys.RootNamespaceID {
return GetZoneConfig(cfg, keys.RootNamespaceID)
}
// No descriptor or not a table.
return config.ZoneConfig{}, false, nil
}
func getTableDescriptor(db *client.DB, database string, table string) *sqlbase.TableDescriptor {
dbNameKey := sqlbase.MakeNameMetadataKey(keys.RootNamespaceID, database)
gr, err := db.Get(dbNameKey)
if err != nil {
panic(err)
}
if !gr.Exists() {
panic("database missing")
}
dbDescID := sqlbase.ID(gr.ValueInt())
tableNameKey := sqlbase.MakeNameMetadataKey(dbDescID, table)
gr, err = db.Get(tableNameKey)
if err != nil {
panic(err)
}
if !gr.Exists() {
panic("table missing")
}
descKey := sqlbase.MakeDescMetadataKey(sqlbase.ID(gr.ValueInt()))
desc := &sqlbase.Descriptor{}
if err := db.GetProto(descKey, desc); err != nil {
panic("proto missing")
}
return desc.GetTable()
}
// RenameDatabase renames the database.
// Privileges: security.RootUser user.
// Notes: postgres requires superuser, db owner, or "CREATEDB".
// mysql >= 5.1.23 does not allow database renames.
func (p *planner) RenameDatabase(n *parser.RenameDatabase) (planNode, error) {
if n.Name == "" || n.NewName == "" {
return nil, errEmptyDatabaseName
}
if p.session.User != security.RootUser {
return nil, fmt.Errorf("only %s is allowed to rename databases", security.RootUser)
}
dbDesc, err := p.getDatabaseDesc(string(n.Name))
if err != nil {
return nil, err
}
if dbDesc == nil {
return nil, databaseDoesNotExistError(string(n.Name))
}
if n.Name == n.NewName {
// Noop.
return &emptyNode{}, nil
}
// Now update the nameMetadataKey and the descriptor.
descKey := sqlbase.MakeDescMetadataKey(dbDesc.GetID())
dbDesc.SetName(string(n.NewName))
if err := dbDesc.Validate(); err != nil {
return nil, err
}
newKey := databaseKey{string(n.NewName)}.Key()
oldKey := databaseKey{string(n.Name)}.Key()
descID := dbDesc.GetID()
descDesc := sqlbase.WrapDescriptor(dbDesc)
b := client.Batch{}
b.CPut(newKey, descID, nil)
b.Put(descKey, descDesc)
b.Del(oldKey)
if err := p.txn.Run(&b); err != nil {
if _, ok := err.(*roachpb.ConditionFailedError); ok {
return nil, fmt.Errorf("the new database name %q already exists", string(n.NewName))
}
return nil, err
}
p.setTestingVerifyMetadata(func(systemConfig config.SystemConfig) error {
if err := expectDescriptorID(systemConfig, newKey, descID); err != nil {
return err
}
if err := expectDescriptor(systemConfig, descKey, descDesc); err != nil {
return err
}
return expectDeleted(systemConfig, oldKey)
})
return &emptyNode{}, nil
}
// RenameIndex renames the index.
// Privileges: CREATE on table.
// notes: postgres requires CREATE on the table.
// mysql requires ALTER, CREATE, INSERT on the table.
func (p *planner) RenameIndex(n *parser.RenameIndex) (planNode, error) {
tn, err := n.Index.Table.NormalizeWithDatabaseName(p.session.Database)
if err != nil {
return nil, err
}
tableDesc, err := p.mustGetTableDesc(tn)
if err != nil {
return nil, err
}
normIdxName := sqlbase.NormalizeName(n.Index.Index)
status, i, err := tableDesc.FindIndexByNormalizedName(normIdxName)
if err != nil {
if n.IfExists {
// Noop.
return &emptyNode{}, nil
}
// Index does not exist, but we want it to: error out.
return nil, err
}
if err := p.checkPrivilege(tableDesc, privilege.CREATE); err != nil {
return nil, err
}
if n.NewName == "" {
return nil, errEmptyIndexName
}
normNewIdxName := sqlbase.NormalizeName(n.NewName)
if normIdxName == normNewIdxName {
// Noop.
return &emptyNode{}, nil
}
if _, _, err := tableDesc.FindIndexByNormalizedName(normNewIdxName); err == nil {
return nil, fmt.Errorf("index name %q already exists", n.NewName)
}
if status == sqlbase.DescriptorActive {
tableDesc.Indexes[i].Name = normNewIdxName
} else {
tableDesc.Mutations[i].GetIndex().Name = normNewIdxName
}
if err := tableDesc.SetUpVersion(); err != nil {
return nil, err
}
descKey := sqlbase.MakeDescMetadataKey(tableDesc.GetID())
if err := tableDesc.Validate(p.txn); err != nil {
return nil, err
}
if err := p.txn.Put(descKey, sqlbase.WrapDescriptor(tableDesc)); err != nil {
return nil, err
}
p.notifySchemaChange(tableDesc.ID, sqlbase.InvalidMutationID)
return &emptyNode{}, nil
}
// getKeysForTableDescriptor retrieves the KV keys corresponding
// to the zone, name and descriptor of a table.
func getKeysForTableDescriptor(
tableDesc *sqlbase.TableDescriptor,
) (zoneKey roachpb.Key, nameKey roachpb.Key, descKey roachpb.Key) {
zoneKey = sqlbase.MakeZoneKey(tableDesc.ID)
nameKey = sqlbase.MakeNameMetadataKey(tableDesc.ParentID, tableDesc.GetName())
descKey = sqlbase.MakeDescMetadataKey(tableDesc.ID)
return
}
func getKeysForDatabaseDescriptor(
dbDesc *sqlbase.DatabaseDescriptor,
) (zoneKey roachpb.Key, nameKey roachpb.Key, descKey roachpb.Key) {
zoneKey = sqlbase.MakeZoneKey(dbDesc.ID)
nameKey = sqlbase.MakeNameMetadataKey(keys.RootNamespaceID, dbDesc.GetName())
descKey = sqlbase.MakeDescMetadataKey(dbDesc.ID)
return
}
// GetTableDesc returns the table descriptor for the table with 'id'.
// Returns nil if the descriptor is not present, or is present but is not a
// table.
func GetTableDesc(cfg config.SystemConfig, id sqlbase.ID) (*sqlbase.TableDescriptor, error) {
if descVal := cfg.GetValue(sqlbase.MakeDescMetadataKey(id)); descVal != nil {
desc := &sqlbase.Descriptor{}
if err := descVal.GetProto(desc); err != nil {
return nil, err
}
return desc.GetTable(), nil
}
return nil, nil
}
// createDescriptor implements the DescriptorAccessor interface.
func (p *planner) createDescriptor(plainKey sqlbase.DescriptorKey, descriptor sqlbase.DescriptorProto, ifNotExists bool) (bool, error) {
idKey := plainKey.Key()
// Check whether idKey exists.
gr, err := p.txn.Get(idKey)
if err != nil {
return false, err
}
if gr.Exists() {
if ifNotExists {
// Noop.
return false, nil
}
// Key exists, but we don't want it to: error out.
return false, fmt.Errorf("%s %q already exists", descriptor.TypeName(), plainKey.Name())
}
// Increment unique descriptor counter.
if ir, err := p.txn.Inc(keys.DescIDGenerator, 1); err == nil {
descriptor.SetID(sqlbase.ID(ir.ValueInt() - 1))
} else {
return false, err
}
// TODO(pmattis): The error currently returned below is likely going to be
// difficult to interpret.
//
// TODO(pmattis): Need to handle if-not-exists here as well.
//
// TODO(pmattis): This is writing the namespace and descriptor table entries,
// but not going through the normal INSERT logic and not performing a precise
// mimicry. In particular, we're only writing a single key per table, while
// perfect mimicry would involve writing a sentinel key for each row as well.
descKey := sqlbase.MakeDescMetadataKey(descriptor.GetID())
b := client.Batch{}
descID := descriptor.GetID()
descDesc := sqlbase.WrapDescriptor(descriptor)
if log.V(2) {
log.Infof("CPut %s -> %d", idKey, descID)
log.Infof("CPut %s -> %s", descKey, descDesc)
}
b.CPut(idKey, descID, nil)
b.CPut(descKey, descDesc, nil)
p.setTestingVerifyMetadata(func(systemConfig config.SystemConfig) error {
if err := expectDescriptorID(systemConfig, idKey, descID); err != nil {
return err
}
return expectDescriptor(systemConfig, descKey, descDesc)
})
return true, p.txn.Run(&b)
}
// ReleaseLease the table lease if it is the one registered with
// the table descriptor.
func (sc *SchemaChanger) ReleaseLease(lease sqlbase.TableDescriptor_SchemaChangeLease) error {
err := sc.db.Txn(func(txn *client.Txn) error {
tableDesc, err := sc.findTableWithLease(txn, lease)
if err != nil {
return err
}
tableDesc.Lease = nil
txn.SetSystemConfigTrigger()
return txn.Put(sqlbase.MakeDescMetadataKey(tableDesc.ID), sqlbase.WrapDescriptor(tableDesc))
})
return err
}
// getTableDescFromID retrieves the table descriptor for the table
// ID passed in using an existing txn. Teturns an error if the
// descriptor doesn't exist or if it exists and is not a table.
func getTableDescFromID(txn *client.Txn, id sqlbase.ID) (*sqlbase.TableDescriptor, error) {
desc := &sqlbase.Descriptor{}
descKey := sqlbase.MakeDescMetadataKey(id)
if err := txn.GetProto(descKey, desc); err != nil {
return nil, err
}
table := desc.GetTable()
if table == nil {
return nil, errDescriptorNotFound
}
return table, nil
}
func isDeleted(tableID sqlbase.ID, cfg config.SystemConfig) bool {
descKey := sqlbase.MakeDescMetadataKey(tableID)
val := cfg.GetValue(descKey)
if val == nil {
return false
}
var descriptor sqlbase.Descriptor
if err := val.GetProto(&descriptor); err != nil {
panic("unable to unmarshal table descriptor")
}
table := descriptor.GetTable()
return table.Deleted()
}
func restoreTable(
ctx context.Context,
sst engine.RocksDBSstFileReader,
txn *client.Txn,
table *sqlbase.TableDescriptor,
overwrite bool,
) error {
log.Infof(ctx, "Restoring Table %q", table.Name)
tableStartKey := roachpb.Key(sqlbase.MakeIndexKeyPrefix(table, table.PrimaryIndex.ID))
tableEndKey := tableStartKey.PrefixEnd()
existingDesc, err := txn.Get(sqlbase.MakeDescMetadataKey(table.GetID()))
if err != nil {
return err
}
existingData, err := txn.Scan(tableStartKey, tableEndKey, 1)
if err != nil {
return err
}
if existingDesc.Value != nil || len(existingData) > 0 {
if overwrite {
// We're about to Put the descriptor, so don't bother deleting it.
if err := txn.DelRange(tableStartKey, tableEndKey); err != nil {
return err
}
} else {
return errors.Errorf("table %q already exists", table.Name)
}
}
tableDescKey := sqlbase.MakeDescMetadataKey(table.GetID())
if err := txn.Put(tableDescKey, sqlbase.WrapDescriptor(table)); err != nil {
return err
}
return Import(ctx, sst, txn, engine.MVCCKey{Key: tableStartKey}, engine.MVCCKey{Key: tableEndKey})
}
// TestStoreRangeSplitAtTablePrefix verifies a range can be split at
// UserTableDataMin and still gossip the SystemConfig properly.
func TestStoreRangeSplitAtTablePrefix(t *testing.T) {
defer leaktest.AfterTest(t)()
sCtx := storage.TestStoreContext()
sCtx.TestingKnobs.DisableSplitQueue = true
store, stopper, _ := createTestStoreWithContext(t, sCtx)
defer stopper.Stop()
key := keys.MakeRowSentinelKey(append([]byte(nil), keys.UserTableDataMin...))
args := adminSplitArgs(key, key)
if _, pErr := client.SendWrapped(rg1(store), nil, &args); pErr != nil {
t.Fatalf("%q: split unexpected error: %s", key, pErr)
}
var desc sqlbase.TableDescriptor
descBytes, err := protoutil.Marshal(&desc)
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 := sqlbase.MakeDescMetadataKey(sqlbase.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:
}
}
// ExtendLease for the current leaser.
func (sc *SchemaChanger) ExtendLease(
existingLease sqlbase.TableDescriptor_SchemaChangeLease,
) (sqlbase.TableDescriptor_SchemaChangeLease, error) {
var lease sqlbase.TableDescriptor_SchemaChangeLease
err := sc.db.Txn(func(txn *client.Txn) error {
tableDesc, err := sc.findTableWithLease(txn, existingLease)
if err != nil {
return err
}
lease = sc.createSchemaChangeLease()
tableDesc.Lease = &lease
txn.SetSystemConfigTrigger()
return txn.Put(sqlbase.MakeDescMetadataKey(tableDesc.ID), sqlbase.WrapDescriptor(tableDesc))
})
return lease, err
}
func (p *planner) changePrivileges(
targets parser.TargetList,
grantees parser.NameList,
changePrivilege func(*sqlbase.PrivilegeDescriptor, string),
) (planNode, error) {
descriptors, err := p.getDescriptorsFromTargetList(targets)
if err != nil {
return nil, err
}
for _, descriptor := range descriptors {
if err := p.checkPrivilege(descriptor, privilege.GRANT); err != nil {
return nil, err
}
privileges := descriptor.GetPrivileges()
for _, grantee := range grantees {
changePrivilege(privileges, string(grantee))
}
switch d := descriptor.(type) {
case *sqlbase.DatabaseDescriptor:
if err := d.Validate(); err != nil {
return nil, err
}
case *sqlbase.TableDescriptor:
if err := d.Validate(p.txn); err != nil {
return nil, err
}
if err := d.SetUpVersion(); err != nil {
return nil, err
}
p.notifySchemaChange(d.ID, sqlbase.InvalidMutationID)
}
}
// Now update the descriptors transactionally.
b := p.txn.NewBatch()
for _, descriptor := range descriptors {
descKey := sqlbase.MakeDescMetadataKey(descriptor.GetID())
b.Put(descKey, sqlbase.WrapDescriptor(descriptor))
}
if err := p.txn.Run(b); err != nil {
return nil, err
}
return &emptyNode{}, nil
}
// isRenamed tests if a descriptor is updated by gossip to the specified name
// and version.
func isRenamed(
tableID sqlbase.ID,
expectedName string,
expectedVersion sqlbase.DescriptorVersion,
cfg config.SystemConfig,
) bool {
descKey := sqlbase.MakeDescMetadataKey(tableID)
val := cfg.GetValue(descKey)
if val == nil {
return false
}
var descriptor sqlbase.Descriptor
if err := val.GetProto(&descriptor); err != nil {
panic("unable to unmarshal table descriptor")
}
table := descriptor.GetTable()
return table.Name == expectedName && table.Version == expectedVersion
}
// getDescriptor implements the DescriptorAccessor interface.
func (p *planner) getDescriptor(plainKey sqlbase.DescriptorKey, descriptor sqlbase.DescriptorProto,
) (bool, error) {
gr, err := p.txn.Get(plainKey.Key())
if err != nil {
return false, err
}
if !gr.Exists() {
return false, nil
}
descKey := sqlbase.MakeDescMetadataKey(sqlbase.ID(gr.ValueInt()))
desc := &sqlbase.Descriptor{}
if err := p.txn.GetProto(descKey, desc); err != nil {
return false, err
}
switch t := descriptor.(type) {
case *sqlbase.TableDescriptor:
table := desc.GetTable()
table.MaybeUpgradeFormatVersion()
// TODO(dan): Write the upgraded TableDescriptor back to kv. This will break
// the ability to use a previous version of cockroach with the on-disk data,
// but it's worth it to avoid having to do the upgrade every time the
// descriptor is fetched. Our current test for this enforces compatibility
// backward and forward, so that'll have to be extended before this is done.
if table == nil {
return false, errors.Errorf("%q is not a table", plainKey.Name())
}
if err := table.Validate(p.txn); err != nil {
return false, err
}
*t = *table
case *sqlbase.DatabaseDescriptor:
database := desc.GetDatabase()
if database == nil {
return false, errors.Errorf("%q is not a database", plainKey.Name())
}
if err := database.Validate(); err != nil {
return false, err
}
*t = *database
}
return true, nil
}
// renameDatabase implements the DatabaseAccessor interface.
func (p *planner) renameDatabase(oldDesc *sqlbase.DatabaseDescriptor, newName string) error {
onAlreadyExists := func() error {
return fmt.Errorf("the new database name %q already exists", newName)
}
if isVirtualDatabase(newName) {
return onAlreadyExists()
}
oldName := oldDesc.Name
oldDesc.SetName(newName)
if err := oldDesc.Validate(); err != nil {
return err
}
oldKey := databaseKey{oldName}.Key()
newKey := databaseKey{newName}.Key()
descID := oldDesc.GetID()
descKey := sqlbase.MakeDescMetadataKey(descID)
descDesc := sqlbase.WrapDescriptor(oldDesc)
b := &client.Batch{}
b.CPut(newKey, descID, nil)
b.Put(descKey, descDesc)
b.Del(oldKey)
if err := p.txn.Run(b); err != nil {
if _, ok := err.(*roachpb.ConditionFailedError); ok {
return onAlreadyExists()
}
return err
}
p.setTestingVerifyMetadata(func(systemConfig config.SystemConfig) error {
if err := expectDescriptorID(systemConfig, newKey, descID); err != nil {
return err
}
if err := expectDescriptor(systemConfig, descKey, descDesc); err != nil {
return err
}
return expectDeleted(systemConfig, oldKey)
})
return nil
}
// TestAddingFKs checks the behavior of a table in the non-public `ADD` state.
// Being non-public, it should not be visible to clients, and is therefore
// assumed to be empty (e.g. by foreign key checks), since no one could have
// written to it yet.
func TestAddingFKs(t *testing.T) {
defer leaktest.AfterTest(t)()
params, _ := createTestServerParams()
s, sqlDB, kvDB := serverutils.StartServer(t, params)
defer s.Stopper().Stop()
if _, err := sqlDB.Exec(`
CREATE DATABASE t;
CREATE TABLE t.products (id INT PRIMARY KEY);
INSERT INTO t.products VALUES (1), (2);
CREATE TABLE t.orders (id INT PRIMARY KEY, product INT REFERENCES t.products, INDEX (product));
`); err != nil {
t.Fatal(err)
}
// Step the referencing table back to the ADD state.
ordersDesc := sqlbase.GetTableDescriptor(kvDB, "t", "orders")
ordersDesc.State = sqlbase.TableDescriptor_ADD
ordersDesc.Version++
if err := kvDB.Put(
sqlbase.MakeDescMetadataKey(ordersDesc.ID),
sqlbase.WrapDescriptor(ordersDesc),
); err != nil {
t.Fatal(err)
}
// Generally a referenced table needs to lookup referencing tables to check
// FKs during delete operations, but referencing tables in the ADD state are
// given special treatment.
if _, err := sqlDB.Exec(`DELETE FROM t.products`); err != nil {
t.Fatal(err)
}
// Client should not see the orders table.
if _, err := sqlDB.Exec(
`SELECT * FROM t.orders`,
); !testutils.IsError(err, "table is being added") {
t.Fatal(err)
}
}
// ExtendLease for the current leaser. This needs to be called often while
// doing a schema change to prevent more than one node attempting to apply a
// schema change (which is still safe, but unwise).
func (sc *SchemaChanger) ExtendLease(
existingLease sqlbase.TableDescriptor_SchemaChangeLease,
) (sqlbase.TableDescriptor_SchemaChangeLease, error) {
// Check if there is still time on this lease.
minDesiredExpiration := timeutil.Now().Add(MinSchemaChangeLeaseDuration)
if time.Unix(0, existingLease.ExpirationTime).After(minDesiredExpiration) {
return existingLease, nil
}
// Update lease.
var lease sqlbase.TableDescriptor_SchemaChangeLease
err := sc.db.Txn(func(txn *client.Txn) error {
tableDesc, err := sc.findTableWithLease(txn, existingLease)
if err != nil {
return err
}
lease = sc.createSchemaChangeLease()
tableDesc.Lease = &lease
txn.SetSystemConfigTrigger()
return txn.Put(sqlbase.MakeDescMetadataKey(tableDesc.ID), sqlbase.WrapDescriptor(tableDesc))
})
return lease, err
}
// getDescriptor implements the DescriptorAccessor interface.
func (p *planner) getDescriptor(plainKey sqlbase.DescriptorKey, descriptor sqlbase.DescriptorProto,
) (bool, error) {
gr, err := p.txn.Get(plainKey.Key())
if err != nil {
return false, err
}
if !gr.Exists() {
return false, nil
}
descKey := sqlbase.MakeDescMetadataKey(sqlbase.ID(gr.ValueInt()))
desc := &sqlbase.Descriptor{}
if err := p.txn.GetProto(descKey, desc); err != nil {
return false, err
}
switch t := descriptor.(type) {
case *sqlbase.TableDescriptor:
table := desc.GetTable()
if table == nil {
return false, util.Errorf("%q is not a table", plainKey.Name())
}
*t = *table
case *sqlbase.DatabaseDescriptor:
database := desc.GetDatabase()
if database == nil {
return false, util.Errorf("%q is not a database", plainKey.Name())
}
*t = *database
}
if err := descriptor.Validate(); err != nil {
return false, err
}
return true, nil
}
// Publish updates a table descriptor. It also maintains the invariant that
// there are at most two versions of the descriptor out in the wild at any time
// by first waiting for all nodes to be on the current (pre-update) version of
// the table desc.
// The update closure is called after the wait, and it provides the new version
// of the descriptor to be written. In a multi-step schema operation, this
// update should perform a single step.
// The closure may be called multiple times if retries occur; make sure it does
// not have side effects.
// Returns the updated version of the descriptor.
func (s LeaseStore) Publish(
tableID sqlbase.ID,
update func(*sqlbase.TableDescriptor) error,
logEvent func(*client.Txn) error,
) (*sqlbase.Descriptor, error) {
errLeaseVersionChanged := errors.New("lease version changed")
// Retry while getting errLeaseVersionChanged.
for r := retry.Start(base.DefaultRetryOptions()); r.Next(); {
// Wait until there are no unexpired leases on the previous version
// of the table.
expectedVersion, err := s.waitForOneVersion(tableID, base.DefaultRetryOptions())
if err != nil {
return nil, err
}
desc := &sqlbase.Descriptor{}
// There should be only one version of the descriptor, but it's
// a race now to update to the next version.
err = s.db.Txn(context.TODO(), func(txn *client.Txn) error {
descKey := sqlbase.MakeDescMetadataKey(tableID)
// Re-read the current version of the table descriptor, this time
// transactionally.
if err := txn.GetProto(descKey, desc); err != nil {
return err
}
tableDesc := desc.GetTable()
if tableDesc == nil {
return errors.Errorf("ID %d is not a table", tableID)
}
if expectedVersion != tableDesc.Version {
// The version changed out from under us. Someone else must be
// performing a schema change operation.
if log.V(3) {
log.Infof(context.TODO(), "publish (version changed): %d != %d", expectedVersion, tableDesc.Version)
}
return errLeaseVersionChanged
}
// Run the update closure.
if err := update(tableDesc); err != nil {
return err
}
// Bump the version and modification time.
tableDesc.Version++
now := s.clock.Now()
tableDesc.ModificationTime = now
if log.V(3) {
log.Infof(context.TODO(), "publish: descID=%d (%s) version=%d mtime=%s",
tableDesc.ID, tableDesc.Name, tableDesc.Version, now.GoTime())
}
if err := tableDesc.ValidateTable(); err != nil {
return err
}
// Write the updated descriptor.
txn.SetSystemConfigTrigger()
b := txn.NewBatch()
b.Put(descKey, desc)
if logEvent != nil {
// If an event log is required for this update, ensure that the
// descriptor change occurs first in the transaction. This is
// necessary to ensure that the System configuration change is
// gossiped. See the documentation for
// transaction.SetSystemConfigTrigger() for more information.
if err := txn.Run(b); err != nil {
return err
}
if err := logEvent(txn); err != nil {
return err
}
return txn.Commit()
}
// More efficient batching can be used if no event log message
// is required.
return txn.CommitInBatch(b)
})
switch err {
case nil, errDidntUpdateDescriptor:
return desc, nil
case errLeaseVersionChanged:
// will loop around to retry
default:
return nil, err
}
}
panic("not reached")
}
func TestDatabaseDescriptor(t *testing.T) {
defer leaktest.AfterTest(t)()
params, _ := createTestServerParams()
s, sqlDB, kvDB := serverutils.StartServer(t, params)
defer s.Stopper().Stop()
expectedCounter := int64(keys.MaxReservedDescID + 1)
// Test values before creating the database.
// descriptor ID counter.
if ir, err := kvDB.Get(keys.DescIDGenerator); err != nil {
t.Fatal(err)
} else if actual := ir.ValueInt(); actual != expectedCounter {
t.Fatalf("expected descriptor ID == %d, got %d", expectedCounter, actual)
}
// Database name.
nameKey := sqlbase.MakeNameMetadataKey(keys.RootNamespaceID, "test")
if gr, err := kvDB.Get(nameKey); err != nil {
t.Fatal(err)
} else if gr.Exists() {
t.Fatal("expected non-existing key")
}
// Write a descriptor key that will interfere with database creation.
dbDescKey := sqlbase.MakeDescMetadataKey(sqlbase.ID(expectedCounter))
dbDesc := &sqlbase.Descriptor{
Union: &sqlbase.Descriptor_Database{
Database: &sqlbase.DatabaseDescriptor{
Name: "sentinel",
ID: sqlbase.ID(expectedCounter),
Privileges: &sqlbase.PrivilegeDescriptor{},
},
},
}
if err := kvDB.CPut(dbDescKey, dbDesc, nil); err != nil {
t.Fatal(err)
}
// Database creation should fail, and nothing should have been written.
if _, err := sqlDB.Exec(`CREATE DATABASE test`); !testutils.IsError(err, "unexpected value") {
t.Fatalf("unexpected error %v", err)
}
if ir, err := kvDB.Get(keys.DescIDGenerator); err != nil {
t.Fatal(err)
} else if actual := ir.ValueInt(); actual != expectedCounter {
t.Fatalf("expected descriptor ID == %d, got %d", expectedCounter, actual)
}
start := roachpb.Key(keys.MakeTablePrefix(uint32(keys.NamespaceTableID)))
if kvs, err := kvDB.Scan(start, start.PrefixEnd(), 0); err != nil {
t.Fatal(err)
} else {
if a, e := len(kvs), server.GetBootstrapSchema().SystemDescriptorCount(); a != e {
t.Fatalf("expected %d keys to have been written, found %d keys", e, a)
}
}
// Remove the junk; allow database creation to proceed.
if err := kvDB.Del(dbDescKey); err != nil {
t.Fatal(err)
}
if _, err := sqlDB.Exec(`CREATE DATABASE test`); err != nil {
t.Fatal(err)
}
expectedCounter++
// Check keys again.
// descriptor ID counter.
if ir, err := kvDB.Get(keys.DescIDGenerator); err != nil {
t.Fatal(err)
} else if actual := ir.ValueInt(); actual != expectedCounter {
t.Fatalf("expected descriptor ID == %d, got %d", expectedCounter, actual)
}
// Database name.
if gr, err := kvDB.Get(nameKey); err != nil {
t.Fatal(err)
} else if !gr.Exists() {
t.Fatal("key is missing")
}
// database descriptor.
if gr, err := kvDB.Get(dbDescKey); err != nil {
t.Fatal(err)
} else if !gr.Exists() {
t.Fatal("key is missing")
}
// Now try to create it again. We should fail, but not increment the counter.
if _, err := sqlDB.Exec(`CREATE DATABASE test`); err == nil {
t.Fatal("failure expected")
}
// Check keys again.
// descriptor ID counter.
if ir, err := kvDB.Get(keys.DescIDGenerator); err != nil {
t.Fatal(err)
} else if actual := ir.ValueInt(); actual != expectedCounter {
t.Fatalf("expected descriptor ID == %d, got %d", expectedCounter, actual)
}
// Database name.
if gr, err := kvDB.Get(nameKey); err != nil {
t.Fatal(err)
} else if !gr.Exists() {
t.Fatal("key is missing")
}
// database descriptor.
if gr, err := kvDB.Get(dbDescKey); err != nil {
t.Fatal(err)
} else if !gr.Exists() {
t.Fatal("key is missing")
}
}