Method RowIter

server/node/drop_type.go:72–164

RowIter implements the interface sql.ExecSourceRel.

(ctx *sql.Context, r sql.Row)

// RowIter implements the interface sql.ExecSourceRel.
func (c *DropType) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
	var userRole auth.Role
	auth.LockRead(func() {
		userRole = auth.GetRole(ctx.Client().User)
	})
	if !userRole.IsValid() {
		return nil, errors.Errorf(`role "%s" does not exist`, ctx.Client().User)
	}

	currentDb := ctx.GetCurrentDatabase()
	if len(c.database) > 0 && c.database != currentDb {
		return nil, errors.Errorf("DROP TYPE is currently only supported for the current database")
	}
	schema, err := core.GetSchemaName(ctx, nil, c.schName)
	if err != nil {
		return nil, err
	}
	collection, err := core.GetTypesCollectionFromContext(ctx, "")
	if err != nil {
		return nil, err
	}
	typeID := id.NewType(schema, c.typName)
	typ, err := collection.GetType(ctx, typeID)
	if err != nil {
		return nil, err
	}
	if typ == nil {
		if c.ifExists {
			// TODO: issue a notice
			return sql.RowsToRowIter(), nil
		} else {
			return nil, types.ErrTypeDoesNotExist.New(c.typName)
		}
	}
	if c.cascade {
		// TODO: handle cascade
		return nil, errors.Errorf(`cascading type drops are not yet supported`)
	}

	if _, ok := types.IDToBuiltInDoltgresType[typ.ID]; ok {
		return nil, types.ErrCannotDropSystemType.New(typ.String())
	}

	// TODO: use .IsArrayType() when we support OIDs, so Elem OID isn't 0
	if typ.TypCategory == types.TypeCategory_ArrayTypes {
		// TODO: get the base type name
		//  add HINT:  You can drop type ___ instead. (base type)
		arrTypeName := typ.String()
		return nil, types.ErrCannotDropArrayType.New(arrTypeName, strings.TrimSuffix(arrTypeName, "[]"))
	}

	// iterate on all table columns to check if this type is currently used.
	db, err := core.GetSqlDatabaseFromContext(ctx, "")
	if err != nil {
		return nil, err
	}
	tableNames, err := db.GetTableNames(ctx)
	if err != nil {