AlterQuery  t1 (children 3)
 ExpressionList (children 1)
  AlterCommand UPDATE (children 2)
   Function or (children 1)
    ExpressionList (children 2)
     Literal UInt64_1
     Function not (children 1)
      ExpressionList (children 1)
       Function not (children 1)
        ExpressionList (children 1)
         Function exists (children 1)
          ExpressionList (children 1)
           Subquery (children 1)
            SelectWithUnionQuery (children 1)
             ExpressionList (children 1)
              SelectQuery (children 3)
               ExpressionList (children 1)
                Identifier key
               TablesInSelectQuery (children 1)
                TablesInSelectQueryElement (children 1)
                 TableExpression (children 1)
                  TableIdentifier t0
               Function greater (children 1)
                ExpressionList (children 2)
                 Identifier key
                 Literal UInt64_0
   ExpressionList (children 1)
    Assignment key (children 1)
     Literal UInt64_0
 Identifier t1
 Set
