Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 1)
    ExpressionList (children 1)
     Function CAST (alias c) (children 1)
      ExpressionList (children 2)
       Function multiply (children 1)
        ExpressionList (children 2)
         Function CAST (children 1)
          ExpressionList (children 2)
           Literal \'0.1\'
           Literal \'Decimal(4, 4)\'
         Literal UInt64_5
       Literal \'Float64\'