| DBIx::Simple::Examples - Examples of how to use DBIx::Simple |
DBIx::Simple::Examples - Examples of how to use DBIx::Simple
DBIx::Simple provides a simplified interface to DBI, Perl's powerful database module.
#!/usr/bin/perl -w
use strict;
use DBIx::Simple;
# Instant database with DBD::SQLite
my $db = DBIx::Simple->connect('dbi:SQLite:dbname=file.dat')
or die DBIx::Simple->error;
# Connecting to a MySQL database
my $db = DBIx::Simple->connect(
'DBI:mysql:database=test', # DBI source specification
'test', 'test', # Username and password
{ RaiseError => 1 } # Additional options
);
# Using an existing database handle
my $db = DBIx::Simple->connect($dbh);
# Abstracted example: $db->query($query, @variables)->what_you_want;
$db->commit or die $db->error;
$db->query('DELETE FROM foo WHERE id = ?', $id) or die $db->error;
for (1..100) {
$db->query(
'INSERT INTO randomvalues VALUES (?, ?)',
int rand(10),
int rand(10)
) or die $db->error;
}
$db->query(
'INSERT INTO sometable VALUES (??)',
$first, $second, $third, $fourth, $fifth, $sixth
);
# (??) is expanded to (?, ?, ?, ?, ?, ?) automatically
my ($two) = $db->query('SELECT 1 + 1')->list;
my ($three, $four) = $db->query('SELECT 3, 2 + 2')->list;
my ($name, $email) = $db->query(
'SELECT name, email FROM people WHERE email = ? LIMIT 1',
$mail
)->list;
Or, more efficiently:
$db->query('SELECT 1 + 1')->into(my $two);
$db->query('SELECT 3, 2 + 2')->into(my ($three, $four));
$db->query(
'SELECT name, email FROM people WHERE email = ? LIMIT 1',
$mail
)->into(my ($name, $email));
my @names = $db->query('SELECT name FROM people WHERE id > 5')->flat;
for my $row ($db->query('SELECT name, email FROM people')->arrays) {
print "Name: $row->[0], Email: $row->[1]\n";
}
for my $row ($db->query('SELECT name, email FROM people')->hashes) {
print "Name: $row->{name}, Email: $row->{email}\n";
}
{
my $result = $db->query('SELECT name, email FROM people');
$result->bind(my ($name, $email));
while ($result->fetch) {
print "Name: $name, Email: $email\n";
}
}
or:
{
my $result = $db->query('SELECT name, email FROM people');
while ($result->into(my ($name, $email))) {
print "Name: $name, Email: $email\n";
}
}
{
my $result = $db->query('SELECT name, email FROM people');
while (my @row = $result->list) {
print "Name: $row[0], Email: $row[1]\n";
}
}
{
my $result = $db->query('SELECT name, email FROM people');
while (my $row = $result->array) {
print "Name: $row->[0], Email: $row->[1]\n";
}
}
{
my $result = $db->query('SELECT name, email FROM people');
while (my $row = $result->hash) {
print "Name: $row->{name}, Email: $row->{email}\n";
}
}
my $customers =
$db
-> query('SELECT id, name, location FROM people')
-> map_hashes('id');
# $customers = { $id => { name => $name, location => $location } }
my $customers =
$db
-> query('SELECT id, name, location FROM people')
-> map_arrays(0);
# $customers = { $id => [ $name, $location ] }
my $names =
$db
-> query('SELECT id, name FROM people')
-> map;
# $names = { $id => $name }
If you have SQL::Interp installed, you can use the semi-abstracting method
iquery. This works just like query, but with parts of the query
interleaved with the bind arguments, passed as references.
You should read the SQL::Interp manpage. These examples are not enough to fully understand all the possibilities.
The following examples are based on the documentation of SQL::Interp.
my $result = $db->iquery('INSERT INTO table', \%item);
my $result = $db->iquery('UPDATE table SET', \%item, 'WHERE y <> ', \2);
my $result = $db->iquery('DELETE FROM table WHERE y = ', \2);
# These two select syntax produce the same result
my $result = $db->iquery('SELECT * FROM table WHERE x = ', \$s, 'AND y IN', \@v);
my $result = $db->iquery('SELECT * FROM table WHERE', {x => $s, y => \@v});
for ($result->hashes) { ... }
Use a syntax highlighting editor for good visual distinction.
If you need the helper functions sql and sql_type, you can import them
with use SQL::Interp;
If you have SQL::Abstract installed, you can use the abstracting methods
select, insert, update, delete. These work like query, but
instead of a query and bind arguments, use abstracted arguments.
You should read the SQL::Abstract manpage. These examples are not enough to fully understand all the possibilities.
The SQL::Abstract object is available (writable) through the abstract
property.
The following examples are based on the documentation of SQL::Abstract.
If you don't like the defaults, just assign a new object:
$db->abstract = SQL::Abstract->new(
case => 'lower',
cmp => 'like',
logic => 'and',
convert => 'upper'
);
If you don't assign any object, one will be created automatically using the default options. The SQL::Abstract module is loaded on demand.
my $result = $db->select($table, \@fields, \%where, \@order);
my $result = $db->insert($table, \%fieldvals || \@values);
my $result = $db->update($table, \%fieldvals, \%where);
my $result = $db->delete($table, \%where);
for ($result->hashes) { ... }
my @tickets = $db->select(
'tickets', '*', {
requestor => 'inna',
worker => ['nwiger', 'rcwe', 'sfz'],
status => { '!=', 'completed' }
}
)->hashes;
If you already have your data as a hash, inserting becomes much easier:
$db->insert('people', \%data);
Instead of:
$db->query(
q[
INSERT
INTO people (name, phone, address, ...)
VALUES (??)
],
@data{'name', 'phone', 'address', ... }
);
$db->update(
'tickets', {
worker => 'juerd',
status => 'completed'
},
{ id => $id }
)
$db->delete('tickets', { id => $id });
The where method is not wrapped directly, because it doesn't generate a
query and thus doesn't really have anything to do with the database module.
But using the abstract property, you can still easily access it:
my $where = $db->abstract->where({ foo => $foo });
If you have DBIx::XHTML_Table installed, you can use the result methods
xto and html.
You should read the DBIx::XHTML_Table manpage. These examples are not enough to fully understand what is going on. When reading that documentation, note that you don't have to pass hash references to DBIx::Simple's methods. It is supported, though.
DBIx::XHTML_Table is loaded on demand.
To print a simple table, all you have to do is:
print $db->query('SELECT * FROM foo')->html;
Of course, anything that produces a result object can be used. The same thing
using the abstraction method select would be:
print $db->select('foo', '*')->html;
A DBIx::XHTML_Table object can be generated with the xto (XHTML_Table
Object) method:
my $table = $db->query($query)->xto;
DBIx::Simple sends the attributes you pass to html both to the constructor
and the output method. This allows you to specify both HTML attributes (like
bgcolor) and options for XHTML_Table (like no_ucfirst and no_indent)
all at once:
print $result->html(
tr => { bgcolor => [ qw/silver white/ ] },
no_ucfirst => 1
);
Not everything can be controlled by passing attributes. For full flexibility, the XHTML_Table object can be used directly:
my $table = $db->query($query)->xto(
tr => { bgcolor => [ qw/silver white/ ] }
);
$table->set_group('client', 1);
$table->calc_totals('credit', '%.2f');
print $table->output({ no_ucfirst => 1 }); # note the {}!
$result->text("neat")neat_list
method. Doesn't display column names.
'1', 'Camel', 'mammal'
'2', 'Llama', 'mammal'
'3', 'Owl', 'bird'
'4', 'Juerd', undef
$result->text("table")
id | animal | type
---+--------+-------
1 | Camel | mammal
2 | Llama | mammal
3 | Owl | bird
4 | Juerd |
$result->text("box")
+----+--------+--------+
| id | animal | type |
+----+--------+--------+
| 1 | Camel | mammal |
| 2 | Llama | mammal |
| 3 | Owl | bird |
| 4 | Juerd | |
+----+--------+--------+
For table and box, you need Anno Siegel's Text::Table module installed.
There is no license. This software was released into the public domain. Do with it what you want, but on your own risk. The author disclaims any responsibility.
Juerd Waalboer <juerd@cpan.org> <http://juerd.nl/>
the DBIx::Simple manpage, the SQL::Abstract manpage
| DBIx::Simple::Examples - Examples of how to use DBIx::Simple |