Explain EXPLAIN PIPELINE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Function count (children 1)
      ExpressionList
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier trivial_count
    Function equals (children 1)
     ExpressionList (children 2)
      Function modulo (children 1)
       ExpressionList (children 2)
        Identifier number
        Literal UInt64_3
      Literal UInt64_2
