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I ave seen a lot of threads discusting the creation of classes for accessing and fetching db fields.
I read a lot of articles... about patterns and stuff... and instead of getting a good solution.. I´m becoming confused...
What is the best way... creating a statement class?
Creating specific classes.. like Article.. Author?
Spliting the aplication into in layers?
Please.. give some help fellows.
Sorry about my english.
This is the way I do it anyways. I've reposted some script I had seen on these forums the other day there, so you have an example to start withCreating specific classes.. like Article.. Author?
Not my script of course, but I cannot remember the thread, nor the person who did post the original scriptPHP Code:...
class PersonMapper {
function &findByLastName($name) {
$sql = 'SELECT id, lastname, firstname ' .
'FROM people ' .
'WHERE lastname LIKE ' . $name .
'ORDER BY lastname';
$rs = $this->db->query($sql);
return $this->loadAll($rs);
}
function &doLoad($row) {
$person = new Person();
$person->setID($row['id']);
$person->setLastName($row['lastname']);
$person->setFirstName($row['firstname']);
return $person;
}
function &loadAll($rs) {
$result = array();
while ($row = $rs->fetch()) {
$result[] = $this->doLoad($row);
}
return $result;
}
}
...
You know who you are though, if you come across this thread you can claim some fame
On the otherhand, the way I do it is like so, below
PHP Code:# login.packages.php
class UserRoles {
function UserRoles() {
} # constructor not implemented
function Load( &$resultset, $archiver ) {
$indexer = array();
$iterator = &new QueryIterator( &$resultset );
while( $iterator -> IsValid() ) {
$row = $iterator -> GetCurrent();
$iterator -> GetNext();
$archive = &new $archiver;
$archive -> Invoke( $row );
$indexer[] = &$archive;
}
return $indexer;
}
function Insert() {
}
function Update() {
}
function Delete() {
}
}
class UserRolesGateway {
function UserRolesGateway() {
} # constructor not implemented
function InsertUsers2Roles( &$db, $role_id, $user_id ) {
$users2Roles = "INSERT INTO tbl_users2roles SET
fld_role_id = '".$role_id."',
fld_user_id = '".$user_id."'";
return $db -> Execute( $users2Roles );
}
function FindAll( &$db ) {
$findAll = "SELECT
fld_id AS id,
fld_role_name AS name FROM
tbl_roles ORDER BY fld_id";
return $db -> Execute( $findAll );
}
function FindByUserId( &$db, $id ) {
$findByUserId = "SELECT
fld_user_id AS user_id,
fld_role_id AS role_id,
fld_id AS id,
fld_role_name AS name FROM
tbl_users2roles,
tbl_roles WHERE
fld_user_id = '".$id."' AND fld_role_id = fld_id ORDER BY fld_role_id";
return $db -> Execute( $findByUserId );
}
}
class RolesArchiver {
var $Id;
var $Name;
function RolesArchiver() {
}
function Invoke( $row ) {
$this -> Id = $row['id'];
$this -> Name = $row['name'];
}
}
class UserPermissions {
function UserPermissions() {
} # constructor not implemented
function Load( &$resultset, $archiver ) {
$indexer = array();
$iterator = &new QueryIterator( &$resultset );
while( $iterator -> IsValid() ) {
$row = $iterator -> GetCurrent();
$iterator -> GetNext();
$archive = &new $archiver;
$archive -> Invoke( $row );
$indexer[] = &$archive;
}
return $indexer;
}
function Insert() {
}
function Update() {
}
function Delete() {
}
}
class UserPermissionsGateway {
function UserPermissionsGateway() {
} # constructor not implemented
function FindByRoleId( &$db, $id ) {
$findByRoleId = "SELECT
fld_perm_id AS perm_id,
fld_role_id AS role_id,
fld_id AS id,
fld_perm_name AS name FROM
tbl_roles2perms,
tbl_permissions WHERE
fld_perm_id = fld_id AND
fld_role_id = '".$id."' ORDER BY fld_perm_id";
return $db -> Execute( $findByRoleId );
}
}
class PermissionsArchiver {
var $Id;
var $Name;
function PermissionsArchiver() {
}
function Invoke( $row ) {
$this -> Id = $row['id'];
$this -> Name = $row['name'];
}
}
class LogIn {
function LogIn() {
} # constructor not implemented
function Load( &$resultset, $archiver ) {
$indexer = array();
$iterator = &new QueryIterator( &$resultset );
while( $iterator -> IsValid() ) {
$row = $iterator -> GetCurrent();
$iterator -> GetNext();
$archive = &new $archiver;
$archive -> Invoke( $row );
$indexer[] = &$archive;
}
return $indexer;
}
function Insert() {
}
function Update() {
}
function Delete() {
}
}
class LogInGateway {
function LogInGateway() {
} # constructor not implemented
function FindByLogIn( &$db, $username, $password ) {
$findByLogIn = "SELECT
fld_id,
UNIX_TIMESTAMP( fld_date ) AS fld_date,
fld_state,
fld_fname,
fld_lname,
fld_email,
fld_session,
fld_username,
fld_password FROM tbl_login WHERE
fld_username = '".$username."' AND
fld_password = PASSWORD('".$password."')";
return $db -> Execute( $findByLogIn );
}
}
class LogInArchiver {
var $Id;
var $Date;
var $State;
var $FName;
var $LName;
var $EMail;
var $Session;
var $Username;
var $Password;
function LogInArchiver() {
} # constructor not implemented
function Invoke( $row ) {
$this -> Id = (int) $row['fld_id'];
$this -> Date = (string) $row['fld_date'];
$this -> State = (string) $row['fld_state'];
$this -> FName = (string) $row['fld_fname'];
$this -> LName = (string) $row['fld_lname'];
$this -> EMail = (string) $row['fld_email'];
$this -> Session = (string) $row['fld_session'];
$this -> Username = (string) $row['fld_username'];
$this -> Password = (string) $row['fld_password'];
}
}
PHP Code:# ie
$db = singleton::getInstance();
$login = LogIn::Load( LogInGateway::FindByLogIn( &$db, $username, $password ), 'LogInArchiver' );
Hey... thanks for the help..
I'm going to look the code later... I probably have a lot to study now...
really, nobody knows. nobody will admit this though. it's why everyone does it slightly different and your largely confused. "the best way" is always slightly different for every case. you can generalize for most cases (i.e. patterns), but they all need to be tweaked to fit your requirements. about the best you can say with any degree of certainty is that it is good to have your data available to your application code without respect to where the data came from (i.e. storage mechanism) or how it got there (which pattern, abstraction, etc.).What is the best way
Before reinventing the wheel, you may want to take a look at Metastorage. This is a data access object generator tool that lets you design models of your data access classes in a simple XML format. Your class models include the variables, validation rules, relationships between classes and functions that implement the aspects that you need to manipulate your data access objects.Originally Posted by Siegfried
Then Metastorage generates all the necessary PHP classes a few seconds, including one to install the database schema with the tables that will store the data access objects.
Other than that, Metastorage features an Object Query Language that lets you perform arbitrary searches for objects of the data classes or belong to specific relation scripts, all without having to write a single line of SQL code by hand.
It also features the ability to generate common types of Web based forms for creating your data objects, generates UML (graphical) diagrams that show all generated classes.
Metastorage in mainly a command line tool but there is now a Web interface to setup and run the Metastorage compiler. Here are some screenshots. BTW, some people do not believe it, but these are really screenshots of the Web interface, not a desktop GUI interface. ;-)
Last edited by mlemos; Jun 17, 2004 at 08:54. Reason: Fixed the screenshots page address.
Manuel Lemos
Metastorage - Data object relational mapping layer generator
PHP Classes - Free ready to use OOP components in PHP
Yes, yes, we are all aware of your Meta storage class(es), and without sounding ignorant or bad mannered, personally I'm fed up to the back teeth of hearing all about it over, and over, and .... over againBefore reinventing the wheel, you may want to take a look at Metastorage. This is a data access object generator tool that lets you design models of your data access classes in a simple XML format. Your class models include the variables, validation rules, relationships between classes and functions that implement the aspects that you need to manipulate your data access objects.
Please, can you change the tune huh ?
To benifit yourself, and to save my sanity maybe Harry or an administrator could post a link in the advanced resources thread, if it hasn't already been done that is ?
Then everyone is happy
You are sounding bad mannered because my message was not meant specifically to you but rather to answer the original poster.Yes, yes, we are all aware of your Meta storage class(es), and without sounding ignorant or bad mannered, personally I'm fed up to the back teeth of hearing all about it over, and over, and .... over again
Please, can you change the tune huh ?
The fact that you are already aware of whatever packages I tell about is perfectly irrelevant. You could just ignore my message. Instead you decided to post a public criticism to my message as if I am not trying to help the original poster and my message is a personal threat to your sanity.
If you really want to me to not try to help other people with my packages, how about stopping the hipocrisy and tell me directly in a private message, instead of making a said spectacle of this thread?
If you do not mind me trying to help other people with my packages, how about just ignoring my messages?
Manuel Lemos
Metastorage - Data object relational mapping layer generator
PHP Classes - Free ready to use OOP components in PHP
Too late.
In fact, I haven't seen it before and it looks like an awesome idea.
Code generation is by far the best idea I've seen. If an entire section of an appliction can be completely generated with no further modification, then when a modificaiton to the specification is required, only a modification to the specification of the code to be generated is needed and you simply re-generate everything.
The ultimate point is to develop faster with less hassle, and this is a brilliant idea.
SorryAppologies all around for any offence caused, none was intended, I assure you
I think this would be a great idea. I can sympathise with Manuel on this issue, but I can also see why it pisses people off.To benifit yourself, and to save my sanity maybe Harry or an administrator could post a link in the advanced resources thread, if it hasn't already been done that is ?
Then everyone is happy
Before criticizing Manuel, do bear in mind that his post is on-topic and that the software he is shamelessly plugging (yes, again & again & again) is open-source, free softare. He's not making a profit from people using his tools and certainly he has invested a lot of time & thought in these products. I don't agree with Manuel's methodology (or lack of tact), but I certainly respect his work.
Moreover, as someone who happens to be lead on a rather similar project, I can understand how it's kinda frustrating to see people post again & again "how do you rcommend I do DAO in PHP?" There are a number of DAO projects in PHP which have invested a lot of thought and sourcecode in the question of how to do this DAO stuff in a good, portable way. So, while it's true that Manuel suggests Metastorage again & again, it's also true that users are asking the same question again & again.
Of course, if a user has a specific question about DAO or found Metastorage (or any of the others) defficient for a particular need, it would be great to hear about that -- and the dialog would be different ('course I'm not saying you wouldn't hear from Manuel
So, I'd just say that before re-creating a basic PHP component, try a search on freshmeat.net or google: "php object persistence", "php dao", "php orm". Of course if you just want to re-create things, then that's different
Cheers,
Hans
Exactly. I fail to see why someone should be criticised for trying to help. One might criticise other posters for "spamming" the boards with a message in almost every topic but nothing to say.
There was 2 points that were a problem for me, which were
1) A running explamation of Metastorage from the point of use of Manuel's classes, which has been posted more than several times over recent months - blatantly promotion if I ever seen it
2) There was no other solution given either, something which I've noted as well in Manuel's postings.
But anyways, it's all water under the bridge so to speak, I'm not one for holding a grudge, etc
This is offtopic but, is doing something like this:
The same as doing this:Code:$var::class_function();
When calling a class function or something? I noticed it in some of the code examples you have...Code:$var->class_function();
-Melchior (Stephen Craton)
Yes and I agree that those are good points. I know why it irritates people; it's the same case on mailing lists like php-db. Certainly Manuel has garnished a reputation for this broadcast-style product promotion.1) A running explamation of Metastorage from the point of use of Manuel's classes, which has been posted more than several times over recent months - blatantly promotion if I ever seen it
2) There was no other solution given either, something which I've noted as well in Manuel's postings.
I think the suggestion that there be a link added to the forum you mentioned was a very good one. Indeed, I think people should be aware that Metastorage is out there. I haven't looked much at that forum myself, but perhaps a single post that enumerated the PHP DAO solutions -- with descriptions, such as the one Manuel provided above -- would be great.
Hans
Hi...
Why don't we have a FAQ?
yours, Marcus
Marcus Baker
Testing: SimpleTest, Cgreen, Fakemail
Other: Phemto dependency injector
Books: PHP in Action, 97 things
An FAQ might work well actually, much like Site Points Blogs ?
This is a static method:
This is a normal (non-static?) methodPHP Code:$var::class_function();
A static method is basically just a function that is in a class.PHP Code:$var->class_function();
It can not have references to the class as an object (i.e. $this->). It must be an independant function seperate from the rest of the object.
The point of putting it in a class, is that it would logically belong in the class along with the classes functionality. For example, you might have a DB class with a method 'GetDBMS($arg)' that returns a subclass of DB, so you would call
$db = DB::GetDBMS($arg);
So essentially, a static method, is a lone function that happens to sit inside a class. And can be called with the :: operator
Hope that was somwhat clearer than mud :-P
Regards,
Eli
Made perfect sense actually, thanks for the explanation!
-Melchior (Stephen Craton)
I don't see the point of instantiating a class for SESSIONs so I use a class with all class methods are static, and it works okay
Likewise for the database layers as well btw
Yeh, I use it for DB layers also. But you have to be careful not to use too many static methods in your code, because then you get away from OOP and move back into proceedural mode where you just have lots of functions - even tho it is in a class, it is still just a list of functions.
It does have a place, just use it sparingly
Yes, don't go over the top, though I still see it as being Obj Oriented Programming
Procedural Prog is for the script kiddies, OO Programming is for real developers
Well, I don't see it like that.Procedural Prog is for the script kiddies, OO Programming is for real developers
I've had to modify a lot of awful proceedural code, and realised that 80-90% of time doing modifications on a system with no design is understand the code before even doing any coding. So productivity runs at about 10-20%.
The lack of productivity - and hence job satisfaction - made the jobs annoying instead of fun, and now understand why most of my friends who graduated with me don't ever want to program in their IT careers.
But learning OO Design makes modification fast and efficient. And when it's designed well, its fun and absurdly easy to use.
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