Programming the Perl DBI

Inserting Data

Inserting data into a flat-file database is very straightforward and usually amounts to simply tacking the new data onto the end of the data file. For example, inserting a new megalith record into a colon-delimited file can be expressed as simply as:

#!/usr/bin/perl -w # # ch02/insertmegadata/insertmegadata: Inserts a new record into the # given megalith data file as # colon-separated data # ### Check the user has supplied an argument to scan for ### 1) The name of the file containing the data ### 2) The name of the site to insert the data for ### 3) The location of the site ### 4) The map reference of the site ### 5) The type of site ### 6) The description of the site die "Usage: insertmegadata" ." <data file> <site name> <location> <map reference> <type> <description>\n" unless @ARGV == 6; my $megalithFile = $ARGV[0]; my $siteName = $ARGV[1]; my $siteLocation = $ARGV[2]; my $siteMapRef = $ARGV[3]; my $siteType = $ARGV[4]; my $siteDescription = $ARGV[5]; ### Open the data file for concatenation, and die upon failure open MEGADATA, ">>$megalithFile" or die "Can't open $megalithFile for appending: $!\n"; ### Create a new record my $record = join( ":", $siteName, $siteLocation, $siteMapRef, $siteType, $siteDescription ); ### Insert the new record into the file print MEGADATA "$record\n" or die "Error writing to $megalithFile: $!\n"; ### Close the megalith data file close MEGADATA or die "Error closing $megalithFile: $!"; print "Inserted record for $siteName\n"; exit; ...