2017 Linux summary tutorial_PHP tutorial

linux&php

1. PHP&MySQL

-----PHP built-in MySQL function learning (3)-----

Preparation

$con=mysqli_connect('localhost','root','','info');
if($con){
echo "Connection successful";
}else{
echo "shit";
}
//mysql_close($con);
if(mysqli_select_db($con, 'info ')){
echo "Database selection successful";
}else{
echo "shit2";
}
/*

----mysql_num_rows()

Get the number of rows in the result set

$query=mysqli_query($con, 'select * from test');//Generate the result set

echo mysqli_num_rows($query ; >

mysqli doesn’t seem to be available, please add some

--- PDO, mysql, mysqli in php

PHP-MySQL is the most original Extension for PHP to operate the MySQL database, PHP-MySQLi The i stands for Improvement, which provides relatively advanced functions. As far as Extension is concerned, it also increases security. PDO (PHP Data Object) provides an Abstraction Layer to operate the database

I can’t tell you the specific difference, just search it and have a look

--- -mysqli_affected_rows($con)

The number of affected rows

is generally used for judgment. For example, when the inserted ones are the same, it is displayed as 0; it feels like mysql feedback

Start the following small practice tomorrow

2. Linux

It is still troublesome to install things in the virtual machine.

xshell is finally done. Sure enough, the centos server interface is not so easy to fix. Fortunately, there are noble people

After entering centos6, enter the user name and password and start to solve network connection problems

Forgot the original URL, write it yourself

---

vim /etc/sysconfig/network-scripts/ifcfg-eth0

Enter i to enter writing Mode

change htcp or something to none, change the onboot item to yes

and then enter IPADDR=192.168.0.10

NETMASK=255.255.255.0

GATEWAY=192.168.0.2

The addresses here are all the addresses of my own network. The query method is win r in the windows interface, enter cmd, enter ipconfig/all

Find the corresponding address. If it is a wireless network, look for the wireless network card. If it is wired, look for the wired one. In short, it must correspond; if the network is changed, the corresponding configuration must also change

If found The address is 192.168.0.1

, then input it in Linux and it will become

192.168.0.a a is not 1, just fine

and the gateway behind it is 192.168.0.b b No Equal to 1, not equal to a

Then return to linux in the virtual machine, press esc, enter: wq, save and exit file writing

Enter service network restart, restart the network service

Then go to the cmd window under Windows just now and enter ping 192.168.0.10 (I set this myself, can you enter your own value?)

If it succeeds, the network connection is OK

As for the settings of xshell, it is very simple

Create a new connection, enter 192.168.0.10 for the location of the host, and then remember to store the user name and password, and just test the connection

I have solved the problem of xshell, so happy! I don’t want to write anything else, let’s play with Linux~~~