CreateQuery abc (children 3)
 Identifier abc
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration f1 (children 1)
    DataType String
   ColumnDeclaration f2 (children 1)
    DataType String
 Storage definition (children 2)
  Function MergeTree (children 1)
   ExpressionList
  Identifier f1
