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<TITLE>Web DBI - State-less-ness</TITLE>
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<H1>Web DBI - State-less-ness</H1>
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<LI><H2>No fixed client-server pair
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<LI>Each request can be handled by a different process.
<LI>So can't simply stop fetching rows from $sth when one page is complete and continue fetching from the same $sth when the next page is requested.
<LI>And transactions can't span requests.
<LI>Even if they could you'd have problems with database locks being held etc.
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<LI><H2>Need access to 'accumulated state' somehow:
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<LI>via the client (e.g., hidden form fields - simple but insecure)
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<LI>Can be made safer using encryption or extra field with checksum (e.g. MD5 hash)
</UL><LI>via the server:
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<LI>requires a session id (via cookie or url)
<LI>in the database (records in a session_state table keyed the session id)
<LI>in the web server file system (DBM files etc) if shared across servers
<LI>Need to purge old state info if stored on server, so timestamp it
<LI>See Apache::Session module
</UL><LI>DBI::ProxyServer + connect_cached with session id may suit, one day
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<H2>.</H2>
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