Get Database Definition
Introduction
All the internal work of MDB2_Schema is done over array structures, which
we will call "definition array". Many methods, such as
createDatabase, requires a definition array as
input parameter, instead of a filename. Others take care of the conversion
automatically, accepting both inputs.
For the cases when you need a definition array, there are two avaliable methods to manually generate the definition array, one for each schema source - either a database or a schema file. Obviously you can also write it by hand, it is not intended to be done this way though.
Get Database Definition
You can use getDefinitionFromDatabase() to get
the definition array from an existing database.
<?php
require_once 'MDB2/Schema.php';
$options = array(
'log_line_break' => '<br>',
'idxname_format' => '%s',
'debug' => true,
'quote_identifier' => true,
'force_defaults' => false,
'portability' => false
);
$dsn = 'mysql://root:@localhost/MDB2Example';
$schema =& MDB2_Schema::factory($dsn, $options);
if (PEAR::isError($schema)) {
$error = $schema->getMessage();
} else {
// this method _attempts_ to get the defintition from the database
// make sure you have tested it with your database to see if it
// returns what you expect
$definition = $schema->getDefinitionFromDatabase();
if (PEAR::isError($definition)) {
$error = $definition->getMessage();
}
}
if (isset($error)) {
var_dump($error);
}
$schema->disconnect();
?>
Though you have to use the method with caution, if you use the method on a
database created by hand. Some of the fields might be slightly different,
but once you create your database using MDB2_Schema it is reliable and will
return the same $definition every time.
Parse Database Definition
You can use parseDatabaseDefinitionFile() to get
the definition array from a schema file.
<?php
require_once 'MDB2/Schema.php';
$options = array(
'log_line_break' => '<br>',
'idxname_format' => '%s',
'debug' => true,
'quote_identifier' => true,
'force_defaults' => false,
'portability' => false
);
$dsn = 'mysql://root:@localhost/MDB2Example';
$schema =& MDB2_Schema::factory($dsn, $options);
if (PEAR::isError($schema)) {
$error = $schema->getMessage();
} else {
$definition = $schema->parseDatabaseDefinitionFile('schema.xml');
if (PEAR::isError($definition)) {
$error = $definition->getMessage();
}
}
if (isset($error)) {
var_dump($error);
}
$schema->disconnect();
?>
Although the method accepts more parameters, only the first one is required.