Question

When I need a table to set settings for my app. I always use table with many fields:

create table options (

 id ...
 url ...
 keys ..
 path ...

)

Of course I need one ID (because I have one settings)

Could I use other approach like:

create table options (

 id ...
 field ..

)

When field is for example:

`key => value`

So I don’t need to set many fields ..

BS:
The fields have different types: int text datetime .. etc

Answer 1

Sure, you can do that. Just make sure you cast to the correct type when taking the values out of the database, and, similarly, when inserting or updating them.

PHP example:

// saving a settings value

$max_length = 20;
mysql_query("UPDATE settings SET value = '{$max_length}' WHERE field = 'max_length'");

// obtaining a settings value

$result = mysql_query("SELECT value FROM settings WHERE field = 'max_length'");
$settings = mysql_fetch_assoc($result);
$max_length = (int) $settings['value'];

For the above example, your schema will need a field (varchar) and a value (varchar).