SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function substring (children 1)
     ExpressionList (children 3)
      Identifier s
      Identifier l
      Identifier r
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier tab