In the need of creation of a database and a way to add an interface for interaction with that, today I learned how to work on MySQL.
Also got to work at Perl DBI for interaction with MySQL. Database access steps are similar to those in other languages:
for using MySQl, go here.
once your MySQL database is ready and assuming that you have created the database named mydb (how ? refer the link above !), you can continue for you safari into Perl DBI.
we begin our database programming by connecting to it with following steps.
use DBI; # to use Perl DBI ;
my $dsn = ‘DBI:mysql:mydb:localhost’; # DSN string
my $db_user_name = “myusername”; # user name for db
my $db_password = “mypasswd”; # passwd for db
my $dbh = DBI->connect($dsn, $db_user_name, $db_password); # connect to mydb
Now, we are ready for processing queries and statements on our database.
for a query like ‘select’ which return some record sets, the process is:
$statement = “select * from mytable”;
my $sth = $dbh->prepare($statement);
$sth->execute or die “can’t execute the query: ” . $sth->errstr;
Now for traversing through the records (rows) we have APIs to help:
while(@row = $sth->fetchrow_array) {
# access @row as an array:
# $row[0] is first field(column)
# $row[1] is second field (column) …
}
# … other stuff
$sth->finish; # reinitialize the handle when needed. we are done.
for the queries like ‘insert’ which do not return any records:
$statement = “insert into mytable values(0, “Manoj”, “402A, West Avenue”)”; $dbh->do($statement) or print $DBI::errstr;
finally,
$dbh->disconnect; # disconnect the db.
following are some links that can come to your rescue in case you get toads !
>> http://safari.oreilly.com/1565926994
>> http://www.perl.com/pub/a/1999/10/DBI.html
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