CreateQuery alter_00147 (children 3)
 Identifier alter_00147
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration d (children 2)
    DataType Date
    Function toDate (children 1)
     ExpressionList (children 1)
      Literal \'2015-01-01\'
   ColumnDeclaration n (children 1)
    DataType Nested (children 1)
     ExpressionList (children 1)
      NameTypePair x (children 1)
       DataType String
 Storage definition (children 1)
  Function MergeTree (children 1)
   ExpressionList (children 3)
    Identifier d
    Identifier d
    Literal UInt64_8192