The PHP Data Objects (PDO) extension defines a lightweight, consistent interface for accessing databases in PHP. This library is dedicated to add bolt protocol. This protocol was created by Neo4j and is used by graph databases like Neo4j, Memgraph or Amazon Neptune.
Right now there is no official C/C++ bolt driver and therefore it is not possible to make this library as extension. Even the unofficial driver looks like it is not maintained. Maybe in future it will change but before that you are welcomed to use this one.
- PHP ^8
- Bolt library
You can use composer or download this repository from GitHub and manually implement it.
Run the following command in your project to install the latest applicable version of the package:
composer require stefanak-michal/pdo-bolt
You can use this library as typical PDO, but you have to create instance of \pdo_bolt\PDO which overrides \PDO and
adds bolt scheme.
$pdo = new \pdo_bolt\PDO('bolt:host=localhost;port=7687;appname=pdo-bolt', 'neo4j', 'neo4j');
$stmt = $pdo->prepare('RETURN $n AS num, $s AS str');
$stmt->bindValue('n', 123, \PDO::PARAM_INT);
$stmt->bindValue('s', 'hello');
$stmt->execute();
$stmt->setFetchMode(\PDO::FETCH_ASSOC);
foreach ($stmt AS $row) {
print_r($row);
}
/* output:
Array
(
[num] => 123
[str] => hello
)
*/For more information about how to use PDO follow official documentation at php.net.
| Key | Description |
|---|---|
| host | The hostname on which the database server resides. |
| port | The port number where the database server is listening. |
| dbname | The name of the database. |
| appname | The application name (used as UserAgent). |
| Key | Description |
|---|---|
| auth | Specify authentication method (none/basic/bearer/kerberos). Automatically detected. |
| ssl | Enable encrypted communication and set ssl context options (see php.net) |
| protocol_versions | Specify requested bolt versions. Array of versions as int/float/string. |
Check method annotation for more informations.
You can use this library with Yii framework in very simple way. Just set up in configuration your PDO class.
https://www.yiiframework.com/doc/api/2.0/yii-db-connection#$pdoClass-detail
Supported parameter placeholder for CQL is ? or string with $ prefix.
Don't use placeholder string with : prefix because CQL use : for labels prefix.
Graph database can be in failure state (error code 02001) and any next message is ignored (error code 02002). Instead of destroying PDO instance and creating new, you can call this method.
Automatically converts resource or string into instance of Bytes class.
| Constant | Description |
|---|---|
| PDO::BOLT_PARAM_FLOAT | |
| PDO::BOLT_PARAM_LIST | Array witch consecutive numeric keys from 0. |
| PDO::BOLT_PARAM_DICTIONARY | Object or array which is not list. |
| PDO::BOLT_PARAM_STRUCTURE | Class extending IStructure. |
| PDO::BOLT_PARAM_BYTES | instance of Bytes class. |
List of usable parameters depends on graph database you use (Neo4j, Memgraph).
- Fetch mode
PDO::FETCH_LAZY - Fetch mode
PDO::FETCH_NAMED - PDO method
lastInsertId() - PDOStatement method
rowCount() - Scrollable cursor
Standard PDO error codes are related to SQL databases. Graph database have CQL (Cypher query language) and therefore I had to create new list of error codes.
| Error code | Description |
|---|---|
| 01000 | Any authentification error |
| 01001 | Wrong credentials |
| 01002 | Undefined auth type |
| 02000 | Any bolt message error |
| 02001 | Bolt message failure |
| 02002 | Bolt message ignored |
| 03000 | Any transaction error |
| 03001 | Transaction not supported (required bolt>=3 |
| 04000 | Any attribute error |
| 04001 | Attribute not supported |
| 05000 | Any parameter error |
| 05001 | Parameter type not supported |
| 05002 | Parameters placeholder mismatch |
| 06000 | Any fetch error |
| 06001 | Requested fetch column not defined |
| 06002 | Fetch object error |
| 07000 | Any underlying bolt library error |