Ejemplo n.º 1
0
// newV3ResolverFromTableDefinition returns a keyspaceIDResolver for a v3 table.
func newV3ResolverFromTableDefinition(keyspaceSchema *vindexes.KeyspaceSchema, td *tabletmanagerdatapb.TableDefinition) (keyspaceIDResolver, error) {
	if td.Type != tmutils.TableBaseTable {
		return nil, fmt.Errorf("a keyspaceID resolver can only be created for a base table, got %v", td.Type)
	}
	tableSchema, ok := keyspaceSchema.Tables[td.Name]
	if !ok {
		return nil, fmt.Errorf("no vschema definition for table %v", td.Name)
	}
	// the primary vindex is most likely the sharding key, and has to
	// be unique.
	if len(tableSchema.ColumnVindexes) == 0 {
		return nil, fmt.Errorf("no vindex definition for table %v", td.Name)
	}
	colVindex := tableSchema.ColumnVindexes[0]
	if colVindex.Vindex.Cost() > 1 {
		return nil, fmt.Errorf("primary vindex cost is too high for table %v", td.Name)
	}
	unique, ok := colVindex.Vindex.(vindexes.Unique)
	if !ok {
		return nil, fmt.Errorf("primary vindex is not unique for table %v", td.Name)
	}

	// Find the sharding key column index.
	columnIndex, ok := tmutils.TableDefinitionGetColumn(td, colVindex.Column.Original())
	if !ok {
		return nil, fmt.Errorf("table %v has a Vindex on unknown column %v", td.Name, colVindex.Column)
	}

	return &v3Resolver{
		shardingColumnIndex: columnIndex,
		vindex:              unique,
	}, nil
}
Ejemplo n.º 2
0
// newV2Resolver returns a keyspaceIDResolver for a v2 table.
// V2 keyspaces have a preset sharding column name and type.
func newV2Resolver(keyspaceInfo *topo.KeyspaceInfo, td *tabletmanagerdatapb.TableDefinition) (keyspaceIDResolver, error) {
	if keyspaceInfo.ShardingColumnName == "" {
		return nil, errors.New("ShardingColumnName needs to be set for a v2 sharding key")
	}
	if keyspaceInfo.ShardingColumnType == topodatapb.KeyspaceIdType_UNSET {
		return nil, errors.New("ShardingColumnType needs to be set for a v2 sharding key")
	}
	if td.Type != tmutils.TableBaseTable {
		return nil, fmt.Errorf("a keyspaceID resolver can only be created for a base table, got %v", td.Type)
	}

	// Find the sharding key column index.
	columnIndex, ok := tmutils.TableDefinitionGetColumn(td, keyspaceInfo.ShardingColumnName)
	if !ok {
		return nil, fmt.Errorf("table %v doesn't have a column named '%v'", td.Name, keyspaceInfo.ShardingColumnName)
	}

	return &v2Resolver{keyspaceInfo, columnIndex}, nil
}