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The MySQL command for selecting the maximum value from a column in a table is straightforward. First, here’s how you do it from a command line (or PHPmyAdmin) in MySQL.

For the following example, I have a database called weight_db and in that database a table called my_weight. There are several fields in this table, one if which is called wt and contains weight data. This is the column I want to select the maximum value from, using the max command.

mysql> use weight_db;
Database changed
mysql> SELECT max(wt) FROM my_weight;
+---------+
| max(wt) |
+---------+
|     199 |
+---------+
1 row in set (0.00 sec)

So, it’s simple and straightforward within MySQL. To do anything with this data in PHP is still fairly simple, it just requires another step. Continue reading »

The last tutorial, How to Create a MySQL Database with PHP, showed us how to create a database on the fly. This example will show us how to make the database usable by creating tables in it. The database we previously created was called “bozo.” Yes, as in Bozo the Clown. The first table we’re going to create will be called “famous_clowns.”

Assuming you did the last tutorial, or you have a database called “bozo,” you can run the following code to create a table in it.

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< ?PHP 
 
mysql_connect("localhost", "fred", "fredpw") or die (mysql_error());
mysql_select_db("bozo");
 
$tablename = "famous_clowns";
 
$maketable="CREATE TABLE $tablename (
seed INT NOT NULL AUTO_INCREMENT,
name VARCHAR (30),
country VARCHAR (20),
rating INT (3),
comment VARCHAR (100),
PRIMARY KEY (seed)
);";
 
mysql_query($maketable) or die (mysql_error());
 
?>

Line 3 is the standard line for connecting to MySQL with my fictional user named Fred and his simple password: fredpw. Line 4 selects the database we’ll be creating the table in.

Line 6 just defines a variable we’ll use to name the table. In this case Continue reading »