1. MySQL tutorial

2. Overview Database (MySQL) - DB creation - Add/delete tables
- Add/delete/update records
- View/query records
Web (PHP)
- User front-end
- Add & query code
- Delete & update code

3. Basic MySQL Syntax SHOW DATABASES; USE database_name; SHOW TABLES;
DROP TABLE table_name;

4. Create MySQL Table CREATE TABLE user (name varchar(9) NOT NULL,
id int(6) NOT NULL,
PRIMARY KEY (id),
UNIQUE (id) );

5. Add/Delete/Update Table
INSERT INTO user VALUES (‘bond’, ‘007’);
DELETE FROM user WHERE id=‘007’;
UPDATE user SET name=‘BOND’ WHERE id=‘007’;

6. Query Database SELECT * FROM user;
SELECT * FROM user WHERE name=‘BOND’;
SELECT DISTINCT name FROM user;
SELECT name, id FROM user ORDER BY name;

7. PHP Configuration File
Use a securely positioned ‘config’ file to store variables.
Other PHP pages can link to it and use the variables as their own.
<?
// configuration parameters
// database configuration
$host = "macneill.cs.tcd.ie";
$user = “username";
$pass = “password";
$db = “username_db";
// default contact person
$def_contact = “Karl";
?>

8. PHP Add to DB Code 1 <table cellspacing="5" cellpadding="5">
<form action="addUpdate.php" method="POST">
<tr>
<td valign="top"><b><font size="-1">Title</font></b></td>
<td><textarea name="title" cols="40" rows="2"></textarea></td>
</tr>
<td valign="top"><b><font size="-1">Authors</font></b></td>
<td><textarea name="authors" cols="40" rows="2"></textarea></td> …
<inut type="Submit" name="submit" value="Add"></td></tr>
</form>
</table>

9. PHP Add to DB Code 2 include("conf.php");
<?
include("conf.php");
// form submitted so start processing it
$title = $_POST["title"];
$authors = $_POST["authors"]; …
// set up error list array & validate text input fields
$errorList = array();
$count = 0;
if (!$title) { $errorList[$count] = "Invalid entry: Title"; $count++; }
// set default value for contact person
if (!$contact) { $contact = $def_contact; }
// check for errors & if none found...
if (sizeof($errorList) == 0) {
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");
mysql_select_db($db) or die ("Unable to select database!");
$query = "INSERT INTO papers (title, authors, description, comment, super, bibtex, url, genre)
VALUES ('$title', '$authors', '$description', '$comment', '$super','$bibtex','$url','$genre')";
$result = mysql_query($query) or die ("Error in query: $query. " . mysql_error());
echo "<font size=-1>Addition successful.<br><br> <a href=papers.php>Go back to the main page</a> | <a href=
// close database connection
mysql_close($connection); }
else {// errors occurred}
?>

10. PHP Query Code
include("conf.php");
$connection = mysql_connect($host, $user, $pass) or die ();
mysql_select_db($db) or die ("Unable to select database!");
$query = "SELECT * FROM papers";
$result = mysql_query($query) or die ("Error in query”);
?>
<table cellpadding="0" cellspacing="0" border="0" width="622">
<tr><td bgcolor="990000"><img src="images/spacer.gif" alt="" height="2"></td></tr>
<?
// if records present
if (mysql_num_rows($result) > 0) {
// iterate through resultset & print title with links to edit and delete scripts
while($row = mysql_fetch_object($result))
<font size="-2"><a href="edit.php?id=<? echo $row->id; ?>">edit/view</a> | <a href="delete.php?id=<? echo $row->id; ?>">delete</a></font><p>
<font size="-1"><b><? echo $row->title; ?></b><br>
<font size="-1"><b>-<? echo $row->authors; ?></b>
<br><a href="<? echo $row->url; ?>" target="_blank"> pdf</a>
<br><br><br> </font>
<tr><td bgcolor="990000"><img src="images/spacer.gif" alt="“ height="2"></td></tr> }
// if no records present
else{}
mysql_close($connection);

11. PHP Delete Code include("conf.php");
// form not yet submitted, display initial form with values pre-filled
$id=$_GET['id']; {
// open database connection
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");
// select database
mysql_select_db($db) or die ("Unable to select database!");
// generate and execute query
$query = "DELETE FROM papers WHERE id = '$id'";
$result = mysql_query($query) or die ("Error in query: $query. " . mysql_error());
// close database connection
mysql_close($connection);
// print result
echo "<font size=-1>Deletion successful. <br><br><a href=papers.php>Go back to the main page</a> | <a href= }

12. PHP Update Code 1 $id=$_GET['id']; if (!$submit) {
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");
mysql_select_db($db) or die ("Unable to select database!");
$query = "SELECT title, authors, description, comment, super, bibtex, url, genre FROM papers WHERE id = '$id'";
$result = mysql_query($query) or die ("Error in query: $query. " . mysql_error())
if (mysql_num_rows($result) > 0)
$row = mysql_fetch_object($result);
// print form with values pre-filled
?>
<table cellspacing="5" cellpadding="5">
<form action="Update.php" method="POST">
<input type="hidden" name="id" value="<? echo $id; ?>">
<tr>
<td valign="top"><b><font size="-1">Title</font></b></td>
<td><textarea name="title" cols="40" rows="2"><? echo $row->title; ?></textarea></td>
</tr>
<td valign="top"><b><font size="-1">Authors</font></b></td>
<td><textarea name="authors" cols="40" rows="2"><? echo $row >authors; ?></textarea></td> …
<td colspan=2>
<input type="Submit" name="submit" value="Update"></td></tr>
</form>
</table>

13. PHP Update Code 2 include("conf.php");
// form submitted so start processing it
$title = $_POST["title"];
$authors = $_POST["authors"]; …
$id = $_POST["id"];
// set up error list array
$errorList = array();
$count = 0;
// validate text input fields
if (!$title) { $errorList[$count] = "Invalid entry: Title"; $count++; }
if (!$contact) { $contact = $def_contact; }
// check for errors, if none found...
if (sizeof($errorList) == 0) {
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");
mysql_select_db($db) or die ("Unable to select database!");
$query = "UPDATE papers SET title = '$title', authors = '$authors', description = '$description', comment = '$comment', super = '$super', bibtex = '$bibtex', url = '$url', genre = '$genre' WHERE id = '$id'";
$result = mysql_query($query) or die ("Error in query: $query. " . mysql_error());
// print result
echo "<font size=-1>Update successful.<br><br> <a href=papers.php>Go back to the main page</a> | <a href=
// close database connection
mysql_close($connection); }
else{}
?>

14. Summary Create MySQL database(s) with tables as required.
Create PHP powered webpage for adding, deleting, updating and viewing database information.
Be aware or security concerns vis-à-vis configuration file contents and database info.