CreateQuery modify_sample (children 3)
 Identifier modify_sample
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration d (children 2)
    DataType Date
    Literal \'2000-01-01\'
   ColumnDeclaration x (children 1)
    DataType UInt8
 Storage definition (children 3)
  Function MergeTree
  Identifier d
  Identifier x
