[Sqlrelay-discussion] Question on Suspending and Resuming SqlRelay Sessions in PHP

[Himsl, J. <jas...@mc...>]

Hello,

I have run into an interesting series of problems implementing
sqlrelay's suspend/resume functions.

My development environment consists of the following:
1) A Debian server running Apache with PHP 4.3.4
2) The same Debian server running sqlrelay (4 pooled connections to the
DB)
3) A Solaris server running Oracle 9.2


Scenario:

I'm trying to create a dynamic page where users can run an Oracle
procedure and view an ordered subset of the records returned on a per
page basis. Users would be shown (x) number of records and be able to
click a link which would return the next (x) set of records from the
original RecordSet.=20

SqlRelay's suspend/resume functionality supposedly allows for the same
RecordSet session to be suspended and resumed across pages without
having to run the DB procedure multiple times. The sqlrelay
documentation gives a small example on how to suspend and resume a
simple insert session. Basically you store the connection vars (RSID,
Port, Socket), call the suspend functions and clear your resources. On
the next page you call the resume functions passing the appropriate
RecordSetID, Port and Socket values to retrieve the suspended Session's
RecordSet. The example was quite vague on how to actually pass the
appropriate RecordSetID, Port and Socket values though. The example also
referenced incorrect function names and parameters to retrieve the port
and socket from the current connection.=20

I thumbed through the API and found the correct function names for
retrieving the Port and Socket information. However, I have found the
return values for both functions to be horribly inconsistent. In most
instances calling the 'sqlrcon_getConnectionSocket' function will
segfault Apache, display garbage characters or even display text values
from the RecordSet. Also calling 'sqlrcon_getConnectionPort' almost
never returns a valid port number and a lot of the time it only returns
0. Keep in mind these are values pulled from a working sqlrelay
connection which successfully queries the database and returns a valid
RecordSet. I am bewildered as to why the 'sqlrcon_getConnectionSocket'
function is returning anything other then null or empty string. Since
sqlrelay runs on a separate server than the database, the sqlrelay
connections should only rely on the hostname and port number. It should
not be using Unix Sockets at all. I'm assuming that the connection
session we are suspending is the connection between sqlrelay and the
Database. Please correct me if I am wrong in this assumption.

I have a slightly different scenario then what was given in the sqlrelay
example. I'm calling an Oracle procedure which returns a refcursor that
I bind a sqlrelay cursor to too. After some experimenting I have
suspended and resumed a RecordSet within the same page call. However,
once I attempted to split the Suspend and Resume functions across pages
I get nothing but 'Unknown errors' from the debugger and Segfaults from
Apache.  I believe I have narrowed the problem down to the sqlrelay
connection object. This all comes back to the
'sqlrcon_getConnectionPort' and 'sqlrcon_getConnectionSocket' functions.

Passing the RecordSetID and Connection Port to another page in PHP is
trivial since they are simple value types. The Connection Socket is
another issue though. PHP considers Unix Sockets to be resources.
Resources can not be serialized in PHP and therefore can not be stored
in a session or passed as a value to the GET or POST vars.=20


Here are my questions:

Why do I see or what would cause so many inconsistencies in the values
returned by the 'sqlrcon_getConnectionPort' and
'sqlrcon_getConnectionSocket' functions?

How do I ensure I get either a valid Port or Socket?

How do I effectively pass the Socket information from one PHP page to
another?




J.D.H.