Wilkques/数据库

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详细信息

github.com/wilkques/Database

源代码

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v0.3.5 2022-08-03 09:55 UTC

Requires

  • php: >=5.4

MIT 2627745c97324133fdb058028c92c1b9f4f4f7bf

This package is auto-updated.

Last update: 2024-09-21 08:38:30 UTC

README

Latest Stable Version License

公告

  1. MySQL 仅支持
  2. 数据库操作

环境

  1. php >= 5.4
  2. mysql >= 5.6
  3. PDO 扩展

如何使用

  1. 通过 PHP require
    下载数据库
    下载 EzLoader 并查看如何使用

    require_once "path/to/your/folder/wilkques/Ezloader/src/helpers.php";
require_once "path/to/your/folder/wilkques/Database/src/helpers.php";

loadPHP();

  2. 通过 Composer composer require wilkques/database

    require "vendor/autoload.php";

  3. 开始

    $connection = \Wilkques\Database\Database::connect('<host>', '<username>', '<password>', '<database>', '<port>', '<character>');

// or

$connection = \Wilkques\Database\Database::connect([
    'driver'    => '<DB driver>',   // mysql
    'host'      => '<host>',        // default localhost
    'username'  => '<username>',
    'password'  => '<password>',
    'database'  => '<database>',
    'port'      => '<port>',        // default 3360
    'charset'   => '<character>',   // default utf8mb4
]);

方法

表或从

  1. table 或 from 或 fromSub table 同 from

    $db->table('<table name>');

// or

$db->table('<table name>', '<as name>');

// or

$db->table(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<as name>'
);

// output: select ... from (select ... from <table name>) AS `<as name>`

// same

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->fromSub(
    $dbTable, 
    '<as name>'
);

// output: select ... from (select ... from <table name>) AS `<as name>`

// same

$db->fromSub(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<as name>'
);

// output: select ... from (select ... from <table name>) AS `<as name>`

// or

$db->table([
    function ($query) {
        $query->table('<table name1>');
    },
    function ($query) {
        $query->table('<table name2>');
    },
]);

// output: select ... from (select ... from <table name1>), (select ... from <table name2>)

// or

$db->table([
    '<as name1>' => function ($query) {
        $query->table('<table name1>');
    },
    '<as name2>' => function ($query) {
        $query->table('<table name2>');
    },
]);

// output: select ... from (select ... from <table name1>) AS `<as name1>`, (select ... from <table name2>) AS `<as name2>`

选择

  1. select 或 selectSub

    $db->select(
    '<columnName1>', 
    '<columnName2>', 
    '<columnName3>',
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// output: select <columnName1>, <columnName2>, <columnName3>, (select ...)

// or

$db->select([
    '<as name1>' => '<columnName1>',
    '<as name2>' => '<columnName1>',
]);

// output: select <columnName1> AS `<as name1>`, <columnName2> AS `<as name2>`

// or

$db->select([
    '<columnName1>', 
    '<columnName2>', 
    '<columnName3>',
    function ($query) {
        $query->table('<table name>');
        // do something
    },
    '<as name>' => function ($query) {
        $query->table('<table name>');
        // do something
    },
]);

// output: select <columnName1>, <columnName2>, <columnName3>, (select ...), (select ...) AS `<as name>`

// or

$db->select("`<columnName1>`, `<columnName2>`, `<columnName3>`");

// or

$db->selectSub(
    function ($query) {
        $query->table('<table name>');
        // do something
    },
    '<as name>'
);

// output: select (select ...) AS `<as name>`

  2. selectSub

    $db->selectSub(
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// output: select (select ...)

// or

$db->selectSub(
    function ($query) {
        $query->table('<table name>');
        // do something
    },
    '<as name>'
);

// output: select (select ...) AS `<as name>`

连接

  1. 连接

    $db->from('<table name1>')->join(
    '<table name2>',
    '<table name1>.<column1>', 
    '<table name2>.<column1>'
);

// output: select ... join <table name> ON <table name1>.<column1> = <table name2>.<column1>

// or

$db->from('<table name1>')->join(
    '<table name2>',
    function ($join) {
        $join->on('<table name1>.<column1>', '<table name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<table name2>.<column2>');

        // do something
    }
);

// output: select ... join <table name> ON <table name1>.<column1> = <table name2>.<column1> OR <table name1>.<column2> = <table name2>.<column2>

  2. joinWhere

    $db->from('<table name1>')->joinWhere(
    '<table name2>',
    '<table name1>.<column1>', 
    '<table name2>.<column1>'
);

// output: select ... join <table name> WHERE <table name1>.<column1> = <table name2>.<column1>

// or

$db->from('<table name1>')->joinWhere(
    '<table name2>',
    function ($join) {
        $join->on('<table name1>.<column1>', '<table name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<table name2>.<column2>');

        // do something
    }
);

// output: select ... join <table name> WHERE <table name1>.<column1> = <table name2>.<column1> OR <table name1>.<column2> = <table name2>.<column2>

  3. joinSub

    $db->from('<table name1>')->joinSub(
    function ($query) {
        $query->table('<table name2>');

        // do something
    },
    '<as name2>',
    function (\Wilkques\Database\Queries\JoinClause $join) {
        $join->on('<table name1>.<column1>', '<as name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<as name2>.<column2>');
    }
);

// output: select ... join (select ...) as `<as name2>` ON <table name1>.<column1> = <as name2>.<column1> OR <table name1>.<column2> = <as name2>.<column2>

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->from('<table name1>')->joinSub(
    $dbTable,
    '<as name2>',
    function (\Wilkques\Database\Queries\JoinClause $join) {
        $join->on('<table name1>.<column1>', '<as name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<as name2>.<column2>');
    }
);

// output: select ... join (select ...) as `<as name2>` ON <table name1>.<column1> = <as name2>.<column1> OR <table name1>.<column2> = <as name2>.<column2>

  4. joinSubWhere

    $db->from('<table name1>')->joinSubWhere(
    function ($builder) {
        $builder->table('<table name2>');

        // do something
    },
    '<as name2>',
    function (\Wilkques\Database\Queries\JoinClause $join) {
        $join->on('<table name1>.<column1>', '<as name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<as name2>.<column2>');
    }
);

// output: select ... join (select ...) as `<as name2>` WHERE <table name1>.<column1> = <as name2>.<column1> OR <table name1>.<column2> = <as name2>.<column2>

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->from('<table name1>')->joinSubWhere(
    $dbTable,
    '<as name2>',
    function (\Wilkques\Database\Queries\JoinClause $join) {
        $join->on('<table name1>.<column1>', '<as name2>.<column1>')
        ->orOn('<table name1>.<column2>', '<as name2>.<column2>');
    }
);

// output: select ... join (select ...) as `<as name2>` WHERE <table name1>.<column1> = <as name2>.<column1> OR <table name1>.<column2> = <as name2>.<column2>

  5. leftJoin

    同 join

  6. leftJoinSub

    同 joinSub

  7. leftJoinWhere

    同 join

  8. leftJoinSubWhere

    同 joinSub

  9. rightJoin

    同 join

  10. rightJoinSub

    同 joinSub

  11. rightJoinWhere

    同 join

  12. rightJoinSubWhere

    同 joinSub

  13. crossJoin

    同 join

  14. crossJoinSub

    同 joinSub

  15. crossJoinWhere

    同 join

  16. crossJoinSubWhere

    同 joinSub

where

  1. where

    $db->where([
    ['<columnName1>'],
    ['<columnName2>'],
    ['<columnName3>'],
]);

// output: select ... where (<columnName1> IS NULL AND <columnName2> IS NULL AND <columnName3> IS NULL)

// or

$db->where('<columnName1>');

// output: select ... where (<columnName1> IS NULL)

// or

$db->where([
    ['<columnName1>', '<value1>'],
    ['<columnName2>', '<value2>'],
    ['<columnName3>', '<value3>'],
]);

// or

$db->where([
    ['<columnName1>', '<operator1>', '<value1>'],
    ['<columnName2>', '<operator2>', '<value2>'],
    ['<columnName3>', '<operator3>', '<value3>'],
]);

// or

$db->where('<columnName1>', "<operator>", '<columnValue1>');

// or

$db->where('<columnName1>', '<value1>')
    ->where('<columnName2>', '<value2>')
    ->where('<columnName3>', '<value3>');

// or

$db->where('<columnName1>', "<operator>", '<value1>')
    ->where('<columnName2>', "<operator>", '<value2>')
    ->where('<columnName3>', "<operator>", '<value3>');

// or

$db->where(function ($query) {
    $query->where('<columnName1>', '<value1>')->where('<columnName2>', '<value2>');
});

// output: select ... where (<columnName1> = <value1> AND <columnName2> = <value2>)

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->where($dbTable);

// same

$db->whereExists($dbTable);

// output: select ... where EXISTS (select ...)

// or

$db->where('<columnName>', $dbTable);

// output: select ... where '<columnName>' = (select ...)

// or

$db->where('<columnName>', "<operator>", $dbTable);

// output: select ... where '<columnName>' <operator> (select ...)

// or

$db->where('<columnName>', "<operator>", function ($query) {
    $query->table('<table name>')->where('<columnName1>', '<value1>')->where('<columnName2>', '<value2>');
});

// output: select ... where '<columnName>' <operator> (select ...)

  2. orWhere

    同 where

  3. whereNull

    $db->whereNull('<columnName1>');

  4. orWhereNull

    同 whereNull

  5. whereNotNull

    同 whereNull

  6. orWhereNotNull

    同 whereNotNull

  7. whereIn

    $db->whereIn('<columnName1>', ['<columnValue1>', '<columnValue2>']);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->whereIn('<columnName1>', $dbTable);

// or

$db->whereIn('<columnName1>', function ($query) {
    $query->select('<columnName2>')->table('<table name1>');
});

  8. orWhereIn

    同 whereIn

  9. whereNotIn

    同 whereIn

  10. orWhereNotIn

    同 whereIn

  11. whereBetween

    $db->whereBetween('<columnName1>', ['<columnValue1>', '<columnValue2>']);

  12. orWhereBetween

    同 whereBetween

  13. whereNotBetween

    同 whereBetween

  14. orWhereNotBetween

    同 whereBetween

  15. whereExists

    $db->whereExists(
    function ($query) {
        $query->table('<table name>');
        // do something
});

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->whereExists($dbTable);

// same

$db->where($dbTable);

  16. whereNotExists

    同 whereExists

  17. orWhereExists

    同 whereExists

  18. orWhereNotExists

    同 whereExists

  19. whereLike

    $db->whereLike('<columnName1>', '<columnValue2>');

  20. orWhereLike

    $db->orWhereLike('<columnName1>', '<columnValue2>');

having

  1. having

    $db->having(`<columnName1>`, `<columnValue1>`);

// or

$db->having(`<columnName1>`, "<operator>", `<columnValue1>`);

// or

$db->having(
    `<columnName1>`,
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// or

$db->having(
    `<columnName1>`,
    "<operator>",
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->having(`<columnName1>`, $dbTable);

// or 

$db->having(`<columnName1>`, "<operator>", $dbTable);

  2. orHaving

    $db->orHaving(`<columnName1>`, `<columnValue1>`);

// or

$db->orHaving(`<columnName1>`, "<operator>", `<columnValue1>`);

// or

$db->orHaving(
    `<columnName1>`,
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// or

$db->orHaving(
    `<columnName1>`,
    "<operator>",
    function ($query) {
        $query->table('<table name>');
        // do something
    }
);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->orHaving(`<columnName1>`, $dbTable);

// or 

$db->orHaving(`<columnName1>`, "<operator>", $dbTable);

limit 或 offset

  1. limit

    $db->limit(1); // set query LIMIT

// or

$db->limit(10, 1); // set query LIMIT

  2. offset

    $db->offset(1); // set query OFFSET

group by

  1. groupBy

    $db->groupBy('<columnName1>', 'DESC'); // default ASC

// or

$db->groupBy([
    ['<columnName1>', 'DESC'],
    ['<columnName2>', 'ASC'],
]);

// or

$db->groupBy([
    [
        function ($query) {
            $query->table('<table name>');
            // do something
        }, 
        'DESC'
    ],
    ['<columnName2>', 'ASC'],
]);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->groupBy($dbTable, 'DESC'); // default ASC

// or

$db->groupBy([
    [
        $dbTable, 
        'DESC'
    ],
    ['<columnName2>', 'ASC'],
]);

  2. groupByDesc

    $db->groupByDesc('<columnName1>');

// or

$db->groupByDesc('<columnName1>', '<columnName2>');

// or

$db->groupByDesc(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
);

// or

$db->groupByDesc(['<columnName1>', '<columnName2>']);

// or

$db->groupByDesc([
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
]);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->groupByDesc($dbTable, '<columnName1>'); // default ASC

// or

$db->groupByDesc([
    $dbTable,
    '<columnName1>'
]);

  3. groupByAsc

    $db->groupByAsc('<columnName1>');

// or

$db->groupByAsc('<columnName1>', '<columnName2>');

// or

$db->groupByAsc(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
);

// or

$db->groupByAsc(['<columnName1>', '<columnName2>']);

// or

$db->groupByAsc([
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
]);

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->groupByAsc($dbTable, '<columnName1>'); // default ASC

// or

$db->groupByAsc([
    $dbTable,
    '<columnName1>'
]);

order by

  1. orderBy

    $db->orderBy('<columnName1>', "DESC"); // default ASC

// or

$db->orderBy([
    ['<columnName1>', 'DESC'],
    ['<columnName2>', 'ASC'],
]);

// or

$db->orderBy([
    [
        function ($query) {
            $query->table('<table name>');
            // do something
        }, 
        'DESC'
    ],
    ['<columnName2>', 'ASC'],
]);

  2. orderByDesc

    $db->orderByDesc('<columnName1>');

// or

$db->orderByDesc('<columnName1>', '<columnName2>');

// or

$db->orderByDesc(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
);

// or

$db->orderByDesc(['<columnName1>', '<columnName2>']);

// or

$db->orderByDesc([
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
]);

  3. orderByAsc

    $db->orderByAsc('<columnName1>');

// or

$db->orderByAsc('<columnName1>', '<columnName2>');

// or

$db->orderByAsc(
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
);

// or

$db->orderByAsc(['<columnName1>', '<columnName2>']);

// or

$db->orderByAsc([
    function ($query) {
        $query->table('<table name>');
        // do something
    }, 
    '<columnName2>'
]);

union

  1. union

    $db->union(function ($query) {
    $query->table('<table name>');
    // do something
});

// or

$dbTable = (
    new \Wilkques\Database\Queries\Builder(
        $connection,
        new \Wilkques\Database\Queries\Grammar\Drivers\MySql,
        new \Wilkques\Database\Queries\Processors\Processor,
    )
)->table('<table name1>');

$db->union($dbTable);

  2. unionAll 同 union

获取数据

  1. get

    $db->get(); // get all data

  2. first

    $db->first(); // get first data

  3. find

    $db->find('<id>'); // get find data

更新

  1. update

    $db->where('<columnName1>', "=", '<columnValue1>')
    ->update([
        '<updateColumnName1>' => '<updateColumnValue1>'
    ]);

// or

$db->where('<columnName1>', "=", '<columnValue1>')->first();

$db->update([
    '<updateColumnName1>' => '<updateColumnValue1>'
]);

// or

$db->where('<columnName1>', "=", '<columnValue1>')->first();

$db->update([
    '<updateColumnName1>' => function ($query) {
        $query->table('<table name>')->select('<column name>');

        // do something
    }
]);

  2. increment

    $db->increment('<columnName>');

// or

$db->increment('<columnName>', '<numeric>', [
    '<update column 1>' => 'update value 1',
    '<update column 2>' => 'update value 2',
    ...
]);

  3. decrement

    $db->decrement('<columnName>');

// or

$db->decrement('<columnName>', '<numeric>', [
    '<update column 1>' => 'update value 1',
    '<update column 2>' => 'update value 2',
    ...
]);

插入

  1. insert

    $db->insert([
        '<ColumnName1>' => 'ColumnValue1>',
        '<ColumnName2>' => 'ColumnValue2>',
        ...
    ]);

// or

$db->insert([
    [
        '<ColumnName1>' => 'ColumnValue1>',
        '<ColumnName2>' => 'ColumnValue2>',
        ...
    ],
    [
        '<ColumnName3>' => 'ColumnValue3>',
        '<ColumnName4>' => 'ColumnValue4>',
        ...
    ]
]);

  2. insertSub

    $db->insertSub([
    '<ColumnName1>'
    '<ColumnName2>'
    ...
], function ($query) {
    $query->from('<Sub table name>')->select(
        '<Sub ColumnName1>',
        '<Sub ColumnName2>',
        ...
    )->where('<Sub columnName3>', '<Sub value1>')->where('<Sub columnName4>', '<Sub value2>');
});

// output: Insert <table> (<ColumnName1>, <ColumnName2>) SELECT <Sub ColumnName1>, <Sub ColumnName2> FROM <Sub table name>
// WHERE <Sub columnName3> = <Sub value1> AND <Sub columnName4> = <Sub value2>

删除

  1. delete

    $db->where('<columnName1>', "=", '<columnValue1>')
    ->delete([
        '<deleteColumnName1>' => '<deleteColumnValue1>'
    ]);

// or

$db->where('<columnName1>', "=", '<columnValue1>')->first();

$db->delete();

  2. 软删除

    $db->where('<columnName1>', "=", '<columnValue1>')
    ->softDelete('<deleteColumnName1>', '<date time format>'); // default deleted_at, "Y-m-d H:i:s"

// or

$db->where('<columnName1>', "=", '<columnValue1>')->first();

$db->softDelete('<deleteColumnName1>', '<date time format>'); // default deleted_at, "Y-m-d H:i:s"

  3. reStore 恢复（delete 无法恢复数据）

    $db->where('<columnName1>', "=", '<columnValue1>')
    ->reStore('<deleteColumnName1>'); // default deleted_at

// or

$db->where('<columnName1>', "=", '<columnValue1>')->first();

$db->reStore('<deleteColumnName1>'); // default deleted_at

原始

  1. raw 
    // select

$db->select($db->raw("<sql string in select column>"));

// example

$db->select($db->raw("COUNT(*)"));

// update

$db->update([
    $db->raw("<sql string in select column>"),
]);

SQL 执行

  1. query 设置 SQL 字符串

    $db->query("<SQL String>")->fetch();

// for example

$db->query("SELECT * FROM `<your table name>`")->fetch();

  2. prepare 执行 SQL 字符串

    $db->prepare("<SQL String>")->execute(['<value1>', '<value2>' ...])->fetch();

  3. bindParams 执行 SQL 字符串

    $stat = $db->prepare("<SQL String>");

$stat->bindParams(['<value1>', '<value2>' ...])->execute();

$stat->fetch();

  4. execute 执行 SQL 字符串

SQL 执行结果

  1. fetchNumeric 获取结果键为数字

  2. fetchAssociative 获取结果键值

  3. fetchFirstColumn 获取结果第一列

  4. fetchAllNumeric 获取所有结果键为数字

  5. fetchAllAssociative 获取所有结果键值

  6. fetchAllFirstColumn 获取所有结果第一列

  7. rowCount 获取结果

  8. free PDO 方法 closeCursor PHP PDOStatement::closeCursor

  9. fetch PDOStatement::fetch

  10. fetchAll PDOStatement::fetchAll

查询日志

  1. enableQueryLog 启用查询日志

    $db->enableQueryLog();

  2. getQueryLog 获取所有查询字符串和绑定数据

    $db->getQueryLog();

  3. getParseQueryLog 或 parseQueryLog 获取解析查询日志

    $db->getParseQueryLog();

  4. getLastParseQuery 或 lastParseQuery 获取解析查询

    $db->getLastParseQuery();

锁定

  1. lockForUpdate

    $db->lockForUpdate();

  2. sharedLock

    $db->sharedLock();

分页

  1. currentPage

    $db->currentPage(1); // now page

  2. prePage

    $db->prePage(15); // pre page

  3. getForPage

    $db->getForPage(); // get page data

// or

$db->getForPage('<prePage>', '<currentPage>'); // get page data

事务

  1. beginTransaction

    $db->beginTransaction();

  2. commit

    $db->commit();

  3. rollback

    $db->rollback();

连接

  1. host

    $db->host('<DB host>');

  2. username

    $db->username('<DB username>');

  3. password

    $db->password('<DB password>');

  4. 数据库

    $db->database('<DB name>');

  5. 新建连接

    $db->newConnection();

// or

$db->newConnection("<sql server dns string>");

  6. 重连

    $db->reConnection();

// or

$db->reConnection("<sql server dns string>");

  7. 选择数据库

    $db->selectDatabase('<database>');