CreateQuery sparse_tuple (children 3)
 Identifier sparse_tuple
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration id (children 1)
    DataType UInt64
   ColumnDeclaration t (children 1)
    DataType Tuple (children 1)
     ExpressionList (children 2)
      NameTypePair a (children 1)
       DataType UInt64
      NameTypePair s (children 1)
       DataType String
 Storage definition (children 3)
  Function MergeTree
  Function tuple (children 1)
   ExpressionList
  Set