The db class of ThinkPHP5 is a database operation class that encapsulates PDO. It is very convenient to use. This article will introduce how to use the db class.
1. Connect to the database
There are two ways to connect to the database, one is to configure it in config.php, and the other is to pass in the connection parameters when instantiating the Db class.
Configure in config.php:
return [ // 数据库类型 'type' => 'mysql', // 服务器地址 'hostname' => '127.0.0.1', // 数据库名 'database' => 'test', // 数据库用户名 'username' => 'root', // 数据库密码 'password' => '', // 数据库连接端口 'hostport' => '', ];
Pass in the connection parameters when instantiating the Db class:
use think\Db; $config = [ // 数据库类型 'type' => 'mysql', // 服务器地址 'hostname' => '127.0.0.1', // 数据库名 'database' => 'test', // 数据库用户名 'username' => 'root', // 数据库密码 'password' => '', // 数据库连接端口 'hostport' => '', ]; Db::connect($config);
2. Basic operations
1. Query Operation
use think\Db; //查询一条数据 Db::table('user')->where('id', 1)->find(); //查询多条数据 Db::table('user')->where('age', '>', 18)->select();
2. Insert operation
use think\Db; $data = [ 'username' => 'admin', 'password' => md5('admin'), 'sex' => 1, 'age' => 20, ]; Db::table('user')->insert($data);
3. Update operation
use think\Db; Db::table('user')->where('id', 1)->update(['age' => 21]);
4. Delete operation
use think\Db; Db::table('user')->where('id', 1)->delete();
3. Advanced operation
1.Chain operation
Chain operation can simplify the writing of sql statements.
use think\Db; Db::table('user') ->alias('u') ->join('role r', 'u.role_id=r.id') ->where('u.id', 1) ->field('u.username, r.name') ->find();
2. Debugging methods
In the development environment, we often need to check the execution of sql statements. The Db class provides three debugging methods: getLastSql, getExplain and getSqlLog.
use think\Db; Db::table('user')->getLastSql(); Db::table('user')->where('age', '>', 18)->getExplain(); Db::table('user')->where('age', '>', 18)->select(); Db::table('user')->getLastSql(); print_r(Db::getSqlLog());
The getLastSql method can obtain the last executed sql statement.
The getExplain method can obtain the execution plan of the sql statement.
The getSqlLog method can obtain all executed sql statements and execution time.
4. Summary
The above is how to use the db class of ThinkPHP5. The db class provides a very convenient way to operate the database, and you can choose to use it according to your needs during development. If you encounter problems when using the db class, you can refer to the official documentation or ask questions in the relevant forums.
The above is the detailed content of An article discusses how to use thinkphp5 db class. For more information, please follow other related articles on the PHP Chinese website!