CreateQuery invalid_map_null (children 3)
 Identifier invalid_map_null
 Columns definition (children 1)
  ExpressionList (children 1)
   ColumnDeclaration id (children 1)
    DataType Map (children 1)
     ExpressionList (children 2)
      DataType UInt8
      DataType Nullable (children 1)
       ExpressionList (children 1)
        DataType String
 Storage definition (children 2)
  Function MergeTree
  Identifier id
