CreateQuery xyz (children 3)
 Identifier xyz
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration x (children 1)
    DataType int
   ColumnDeclaration y (children 1)
    DataType int
   ColumnDeclaration z (children 1)
    DataType int
 Storage definition (children 4)
  Function MergeTree
  Function if (children 1)
   ExpressionList (children 3)
    Function toUInt8 (children 1)
     ExpressionList (children 1)
      Identifier x
    Identifier y
    Identifier z
  Identifier x
  Set