我在centos 7.2上安装了php 3.4和mongodb 7.4，
我运行php命令时出错，如下所示：
[root@vagrant-dev ~]# php artisan migrate
PHP Warning: PHP Startup: Unable to load dynamic library 'mongodb.so' (tried: /usr/lib64/php/modules/mongodb.so (/usr/lib64/php/modules/mongodb.so: cannot open shared object file: No such file or directory), /usr/lib64/php/modules/mongodb.so.so (/usr/lib64/php/modules/mongodb.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0
Could not open input file: artisan
我该怎么办？