Connecting to a database with PHP

Connecting to a database with PHP

Install these packages:

#apt-get install apache2
#apt-get install mysql
#apt-get install php
#apt-get install php5-mysql

Create a test user, password and database

At the sql server, Log into mysql:

#mysql -u root -p

Issue the following commands to create a user “test” and a password “password”:

CREATE USER ‘test’@’localhost’ IDENTIFIED BY ‘password’;
CREATE USER ‘test’@’%’ IDENTIFIED BY ‘password’;

GRANT ALL ON *.* TO ‘test’@’localhost’;
GRANT ALL ON *.* TO ‘test’@’%’;

CREATE DATABASE instruments

 

Exit mysql:

q

Log back in as the user you just created, attaching to the new database:

mysql -u test -p instruments

Execute a

s

to see the status. Verify the user and database.

Test PHP Functionality:

Create a file named “something”.php and insert the following text:

<?php echo ‘hello world’.time();
/* <?php echo ‘mysqli_connect(); print_r(mysqli_query(‘select now()’)) ; ?> */
?>

Place this file in the /var/www directory

Open a browser and point to that file:

http://<your server>”something”.php

You should see hello world and the date.

To test your connection to the database via PHP:

Create a file with the following text and name it “something”.php

Edit the line “$db = mysql_connect(“206.207.94.34″,”test”,”password”);” to reflect your server & user.

<?php
$db = mysql_connect(“206.207.94.34″,”test”,”password”);
if (!$db) {
die(“Database connection failed miserably: ” . mysql_error());
}
else

die(“Database Success!!!: ” . mysql_error());
$db_select = mysql_select_db(“instruments”,$db);
if (!$db_select) {
die(“Database selection also failed miserably: ” . mysql_error());
}
?>
<html>
<head>
<title>Step 3</title>
</head>
<body>
<?php
$result = mysql_query(“SELECT * FROM mytable”, $db);
if (!$result) {
die(“Database query failed: ” . mysql_error());
}
?>
</body>
</html>

Place this file in the /var/www directory

Open a browser and point to that file:

http://<your server>”something.php

Success!!!

HANDY MYSQL COMMANDS:

Note that all text commands must be first on line and end with ‘;’
? (?) Synonym for `help’.
clear (c) Clear the current input statement.
connect (r) Reconnect to the server. Optional arguments are db and host.
delimiter (d) Set statement delimiter.
edit (e) Edit command with $EDITOR.
ego (G) Send command to mysql server, display result vertically.
exit (q) Exit mysql. Same as quit.
go (g) Send command to mysql server.
help (h) Display this help.
nopager (n) Disable pager, print to stdout.
notee (t) Don’t write into outfile.
pager (P) Set PAGER [to_pager]. Print the query results via PAGER.
print (p) Print current command.
prompt (R) Change your mysql prompt.
quit (q) Quit mysql.
rehash (#) Rebuild completion hash.
source (.) Execute an SQL script file. Takes a file name as an argument.
status (s) Get status information from the server.
system (!) Execute a system shell command.
tee (T) Set outfile [to_outfile]. Append everything into given outfile.
use (u) Use another database. Takes database name as argument.
charset (C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets.
warnings (W) Show warnings after every statement.
nowarning (w) Don’t show warnings after every statement.

For server side help, type ‘help contents’

Matt Long
01/27/2015