Tie::FieldVals

Tie::FieldVals is a perl Tie object to map the records in an enhanced Field:Value data file into an array. Each file has multiple records, each record has its values defined by a Field:Value pair, with the enhancements that (a) the Value part can extend over more than one line (because the Field names are predefined) and (b) Fields can have multiple values by repeating the Field:Value part for a given field.

The advantage of this setup is that one can have useful data files which are plain text, human readable, human editable, and at the same time able to be accessed faster than using XML (I know, I wrote a version of my reporting software using XML data, and even the fastest XML parsers weren't as fast as this setup, once there were a reasonable number of records). This also has advantages over a simpler setup where values are given one per line with no indication of what value belongs to what field; the problems with that is that it is harder to fix corrupted data by hand, and it is harder to add new fields, and one can't have multi-line data.

It is likewise better than a CSV (Comma-Separated Values) file, because again, with a CSV file, the data is positional and therefore harder to fix and harder to change, and again one can't have multi-line data.

This module is both better and worse than file-oriented databases like DB_File and its variants and extensions (such as MLDBM). This module does not require that each record have a unique key, and the fact that a DBM file is binary makes it not only less correctable, but also less portable. On the downside, this module isn't as fast.

Naturally, if one's data needs are more complex, it is probably better to use a fully-fledged database; this is oriented towards those who don't wish to have the overhead of setting up and maintaining a relational database server, and wish to use something more straightforward.

The Tie::FieldVals module is released under the same conditions as Perl, that is, under the Artistic Licence and the GNU General Public Licence.

This module is also available on CPAN. Just go to my page on CPAN and you will find it under Tie::FieldVals.