func (c *conn) getTableDesc(table *parser.TableName) (*structured.TableDescriptor, error) {
if err := c.normalizeTableName(table); err != nil {
return nil, err
}
dbID, err := c.lookupDatabase(table.Qualifier)
if err != nil {
return nil, err
}
gr, err := c.db.Get(keys.MakeNameMetadataKey(dbID, table.Name))
if err != nil {
return nil, err
}
if !gr.Exists() {
return nil, fmt.Errorf("table \"%s\" does not exist", table)
}
descKey := gr.ValueBytes()
desc := structured.TableDescriptor{}
if err := c.db.GetProto(descKey, &desc); err != nil {
return nil, err
}
if err := structured.ValidateTableDesc(desc); err != nil {
return nil, err
}
return &desc, nil
}
func (db *DB) getTableDesc(path string) (*structured.TableDescriptor, error) {
nsID, name, err := db.lookupTable(path)
if err != nil {
return nil, err
}
if name == "" {
return nil, fmt.Errorf("empty table name: %s", path)
}
gr, err := db.Get(keys.MakeNameMetadataKey(nsID, name))
if err != nil {
return nil, err
}
if !gr.Exists() {
return nil, fmt.Errorf("unable to find table \"%s\"", path)
}
descKey := gr.ValueBytes()
desc := structured.TableDescriptor{}
if err := db.GetProto(descKey, &desc); err != nil {
return nil, err
}
if err := structured.ValidateTableDesc(desc); err != nil {
return nil, err
}
return &desc, nil
}
func (c *conn) CreateTable(p *parser.CreateTable, args []driver.Value) (*rows, error) {
if err := c.normalizeTableName(p.Table); err != nil {
return nil, err
}
dbID, err := c.lookupDatabase(p.Table.Qualifier)
if err != nil {
return nil, err
}
schema, err := makeSchema(p)
if err != nil {
return nil, err
}
desc := structured.TableDescFromSchema(schema)
if err := structured.ValidateTableDesc(desc); err != nil {
return nil, err
}
nameKey := keys.MakeNameMetadataKey(dbID, p.Table.Name)
// This isn't strictly necessary as the conditional put below will fail if
// the key already exists, but it seems good to avoid the table ID allocation
// in most cases when the table already exists.
if gr, err := c.db.Get(nameKey); err != nil {
return nil, err
} else if gr.Exists() {
if p.IfNotExists {
return &rows{}, nil
}
return nil, fmt.Errorf("table \"%s\" already exists", p.Table)
}
ir, err := c.db.Inc(keys.DescIDGenerator, 1)
if err != nil {
return nil, err
}
desc.ID = uint32(ir.ValueInt() - 1)
// TODO(pmattis): Be cognizant of error messages when this is ported to the
// server. The error currently returned below is likely going to be difficult
// to interpret.
err = c.db.Txn(func(txn *client.Txn) error {
descKey := keys.MakeDescMetadataKey(desc.ID)
b := &client.Batch{}
b.CPut(nameKey, descKey, nil)
b.Put(descKey, &desc)
return txn.Commit(b)
})
if err != nil {
// TODO(pmattis): Need to handle if-not-exists here as well.
return nil, err
}
return &rows{}, nil
}
// RenameTable renames a table. Old path and new path have the form
// "<namespace>.<table>".
func (db *DB) RenameTable(oldPath, newPath string) error {
// TODO(pmattis): Should we allow both the old and new name to exist
// simultaneously for a period of time? The thought is to allow an
// application to access the table via either name while the application is
// being upgraded. Alternatively, instead of a rename table operation perhaps
// there should be a link table operation which adds a "hard link" to the
// table. Similar to a file, a table would not be removed until all of the
// hard links are removed.
oldNSID, oldName, err := db.lookupTable(oldPath)
if err != nil {
return err
}
newNSID, newName, err := db.lookupTable(newPath)
if err != nil {
return err
}
if newName == "" {
return fmt.Errorf("empty table name: %s", newPath)
}
return db.Txn(func(txn *Txn) error {
oldNameKey := keys.MakeNameMetadataKey(oldNSID, oldName)
gr, err := txn.Get(oldNameKey)
if err != nil {
return err
}
if !gr.Exists() {
return fmt.Errorf("unable to find table \"%s\"", oldPath)
}
descKey := gr.ValueBytes()
desc := structured.TableDescriptor{}
if err := txn.GetProto(descKey, &desc); err != nil {
return err
}
desc.Name = strings.ToLower(newPath)
if err := structured.ValidateTableDesc(desc); err != nil {
return err
}
newNameKey := keys.MakeNameMetadataKey(newNSID, newName)
b := &Batch{}
b.Put(descKey, &desc)
// If the new name already exists the conditional put will fail causing the
// transaction to fail.
b.CPut(newNameKey, descKey, nil)
b.Del(oldNameKey)
return txn.Commit(b)
})
}
// CreateTable creates a table from the specified schema. Table creation will
// fail if the table name is already in use. The table name is required to have
// the form "<namespace>.<table>".
func (db *DB) CreateTable(schema structured.TableSchema) error {
schema.Name = strings.ToLower(schema.Name)
desc := structured.TableDescFromSchema(schema)
if err := structured.ValidateTableDesc(desc); err != nil {
return err
}
nsID, name, err := db.lookupTable(desc.Name)
if err != nil {
return err
}
if name == "" {
return fmt.Errorf("empty table name: %s", desc.Name)
}
nameKey := keys.MakeNameMetadataKey(nsID, name)
// This isn't strictly necessary as the conditional put below will fail if
// the key already exists, but it seems good to avoid the table ID allocation
// in most cases when the table already exists.
if gr, err := db.Get(nameKey); err != nil {
return err
} else if gr.Exists() {
return fmt.Errorf("table \"%s\" already exists", desc.Name)
}
ir, err := db.Inc(keys.DescIDGenerator, 1)
if err != nil {
return err
}
desc.ID = uint32(ir.ValueInt() - 1)
// TODO(pmattis): Be cognizant of error messages when this is ported to the
// server. The error currently returned below is likely going to be difficult
// to interpret.
return db.Txn(func(txn *Txn) error {
descKey := keys.MakeDescMetadataKey(desc.ID)
b := &Batch{}
b.CPut(nameKey, descKey, nil)
b.Put(descKey, &desc)
return txn.Commit(b)
})
}
