Hacking Google Maps and Google Earth (ExtremeTech)

212 Part III — Google Map Hacks

entitylist();

}

elsif(param(‘m’) eq ‘getmarkers’)

{

getmarkers(param(‘entity’));

}

The entitylist()function returns a list of unique entity types (restaurants, banks, and so

on) that were populated when the database was populated. For that, the SQL statement uses

DISTINCTto get a list of unique types and then formats XML for the Google Maps applica-

tion to extract:

sub entitylist

{

my $sth = $dbh->prepare(‘select distinct(type) from ch11’);

$sth->execute();

print “<types>”;

while (my $row = $sth->fetchrow_hashref())

{

printf(‘<type typename=”%s”/>’,ucfirst($row->{type}));

}

print “</types>”;

}

The getmarkers()function is just a minor alteration from the script in Chapter 9.

sub getmarkers

{

my ($entity) = @_;

print(“<markers>\n”);

my $sth = $dbh->prepare(sprintf(‘select * from ch11 where type = %s’,

$dbh->quote($entity)));

$sth->execute();

while (my $row = $sth->fetchrow_hashref())

{

printf(‘<marker lat=”%f” lng=”%f” title=”%s”> ;

<infowindow><title>%s</title><address>%s</address><city>%s</city> ;

<phone>%s</phone></infowindow></marker>’,

$row->{lat},

$row->{lng},

$row->{title},

$row->{title},

$row->{adda},

$row->{addb},

$row->{tel},

);

}