Re: DBI fetchall_hashref convert to scalar

G'day 3dbc,

I'd take a look at the built-in module Storable.

"The Storable package brings persistence to your Perl data structures containing SCALAR, ARRAY, HASH or REF objects, ..."

And, right after that, the MEMORY STORE section begins:

"The Storable engine can also store data into a Perl scalar instead, to later retrieve them. ..."

— Ken

Comment on Re: DBI fetchall_hashref convert to scalar

Replies are listed 'Best First'.
Re^2: DBI fetchall_hashref convert to scalar by afoken (Chancellor) on Feb 03, 2017 at 13:02 UTC
Storable Storable is ok for short-time storage, e.g. caching stuff that needs a long time to be recalculated. But DBI sounds like long-time storage. OS, platform, and Perl versions may change over time, and because Storable depends on all of these, that will break Storable. Stuffing serialised perl data structures into a database does not sound sane. It means the database is not normalised. Ideally, all data would be stored in database-native formats. Anyway, there are various other formats to serialise data structures that do not depend on the exact perl version, e.g. XML, JSON, YAML. See also: Re: Perl Storable problem (i Think) Re^2: memory persistance Re^3: Portable datastore formats in core perl? Re^4: The safety of string eval and block eval. Re^2: Storing state of execution Re^2: Caching Format Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply]

Replies are listed 'Best First'.

Re^2: DBI fetchall_hashref convert to scalar
by afoken (Chancellor) on Feb 03, 2017 at 13:02 UTC

Storable

Storable is ok for short-time storage, e.g. caching stuff that needs a long time to be recalculated. But DBI sounds like long-time storage. OS, platform, and Perl versions may change over time, and because Storable depends on all of these, that will break Storable.

Stuffing serialised perl data structures into a database does not sound sane. It means the database is not normalised. Ideally, all data would be stored in database-native formats.

Anyway, there are various other formats to serialise data structures that do not depend on the exact perl version, e.g. XML, JSON, YAML.