Codeigniter中如何连接mssql？

Question

I am trying to connect codeigniter with MSSQL. I have done all possible changes in the php.ini file by adding the extensions extension=php_sqlsrv_56_ts.dll and extension=php_pdo_sqlsrv_56_ts.dll . But still am facing sqlsrv error as follow,

Error: Message: sqlsrv_query() expects parameter 1 to be resource, null given

sqlsrv_driver.php

function _execute($sql)
{
    $sql = $this->_prep_query($sql);
    return sqlsrv_query($this->conn_id, $sql, null, array(
        'Scrollable'                => SQLSRV_CURSOR_STATIC,
        'SendStreamParamsAtExec'    => true
    ));
}

$this->conn_id --- this is empty. I don't know why its getting null value.

Codeigniter Version: 2.2 /
PHP Version: 5.6

Database configuration:

$db['default']['hostname'] = '.\sqlexpress';
$db['default']['username'] = 'UNAME';
$db['default']['password'] = '';
$db['default']['database'] = 'DBNAME'; 
$db['default']['dbdriver'] = 'sqlsrv';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = FALSE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

NOTE: I have been stuck in this for past 3 day and i have tried. Since i am new to MSSQL, i cant able to figure out the problem. Any help in this would be much appreciated. Thanks in advance.

Answer 1

You are running an unsupported version of PHP. You need to upgrade your PHP version to continue to receive security updates. See https://php.net/supported-versions.php .

Doing this would also give you access to newer versions of the sqlsrv drivers. This is important because your current driver cannot connect to newer versions of SQL Server.

You've stated you're using SQL 2017. However as per the Microsoft PHP Drivers for SQL Server Support Matrix , with PHP version 5.6 you can only run version 3.2 of the sqlsrv drivers, and version 3.2 of the drivers only supports SQL 2014 and below.