3.9 KiB
Query
A query builder/database abstraction layer, using prepared queries for security.
Requirements
- Pdo extensions for the databases you wish to use (unless it's Firebird, in which case, the interbase extension is required)
- PHP 5.3+
Databases Supported
- Firebird (via interbase extension)
- Firebird (via PDO) -- expirimental
- MySQL
- PostgreSQL
- SQLite
Including Query in your application
To include Query in your PHP project, just include the autoload.php
file. This will automatically load the classes that are supported by the current PHP installation.
Connecting
Create a connection array or object similar to this:
<?php
$params = array(
'type' => 'mysql',
'host' => 'localhost',
'user' => 'root',
'pass' => '',
'port' => '3306',
'database' => 'test_db',
// Only required
// SQLite or Firebird
'file' => '/path/to/db/file',
// Optional paramaters
'prefix' => 'tbl_', // Database table prefix
'alias' => 'old' // Connection name for the Query function
);
$db = Query($params);
The parameters required depend on the database.
Query function
You can use the Query()
function as a reference to the last connected database. E.g.
Query()->get('table_name');
or
$result = Query()->query($sql);
If the alias
key is set in the parameters, you can refer to a specific database connection
// Set the alias in the connection parameters
$params['alias'] = 'old';
// Connect to the legacy database
Query('old')->query($sql);
Running Queries
Query uses the same interface as CodeIgniter's Active Record class. However, it does not implement the update_batch
or caching methods.
####You can also run queries manually.
To run a prepared statement, call
$db->prepare_execute($sql, $params)
.
To run a plain query, $db->query($sql)
Retrieving Results:
An example of a moderately complex query:
$query = $db->select('id, key as k, val')
->from('table t')
->where('k >', 3)
->or_where('id !=' 5)
->order_by('val', 'DESC')
->limit(3, 1)
->get();
This will generate a query similar to (with this being the output for a Postgres database):
SELECT "id", "key" AS "k", "val"
FROM "table" "t"
WHERE "k" > ?
OR "id" != ?
ORDER BY "val" DESC
LIMIT 3 OFFSET 1
To retreive the results of a query, use the PDO method fetch and/or fetchAll.
$query = $db->get('table_name');
$results = $query->fetchAll(PDO::FETCH_ASSOC);
Inserting / Updating
An example of an insert query:
$query = $db->set('foo', 'bar')
->set('foobar', 'baz')
->where('foo !=', 'bar')
->insert('table');
An example of an update query:
$query = $db->set('foo', 'bar')
->set('foobar', 'baz')
->where('foo !=', 'bar')
->update('table');
The set
method can also take an array as a paramater, instead of setting individual values.