Connecting to Vertica using Perl
You use the Perl DBI module's connect function to connect to Vertica. This function takes a required data source string argument and optional arguments for the username, password, and connection attributes.
The data source string must start with "dbi:ODBC:", which tells the DBI module to use the DBD::ODBC driver to connect to the database. The remainder of the string is interpreted by the DBD::ODBC driver. It usually contains the name of a DSN that contains the connection information needed to connect to your database. For example, to tell the DBD::ODBC driver to use the DSN named VerticaDSN, you use the data source string:
"dbi:ODBC:VerticaDSN"
The username and password parameters are optional. However, if you do not supply them (or just the username for a passwordless account) and they are not set in the DSN, attempting to connect always fails.
The connect function returns a database handle if it connects to the database. If it does not, it returns undef. In that case, you can access the DBI module's error string property ($DBI::errstr) to get the error message.
Note
By default, the DBI module prints an error message to STDERR whenever it encounters an error. If you prefer to display your own error messages or handle errors in some other manner, you may want to disable these automatic messages by setting DBI's PrintError connection attribute to false. See Setting Perl DBI connection attributes for details. Otherwise, users may see two error messages: the one that DBI prints automatically, and the one that your script prints on its own.The following example connects to the database with a DSN named VerticaDSN. The call to connect supplies a username and password. After connecting, it calls the database handle's disconnect function, which closes the connection:
#!/usr/bin/perl -w
use strict;
use DBI;
# Open a connection using a DSN. Supply the username and password.
my $dbh = DBI->connect("dbi:ODBC:VerticaDSN","ExampleUser","password123");
unless (defined $dbh) {
# Conection failed.
die "Failed to connect: $DBI::errstr";
}
print "Connected!\n";
$dbh->disconnect();