I'm working on a web site that will have multiple users. Say 5 users total.What I need to make sure is, that each user will only be able to access the data they input.
Think of a CRM or Job Board. So john will only be able to access johns info, edit, add, etc. Same with jane and june.
Now if my reading is correct, all i need to do is make sure the queries pull only the data based off their unique id correct?
so the database table for the users looks like:
Database: xxxxx, Table: xh_user
user_id
user_username
user_fname
users_email
users_password
users_salt
so if johns user_id is 7, when he logs in, it queries his id and displays only his content from the database.
Am i correct on this?, or is there a different or better way to accomplish this?
As long as your foreign keys are setup correctly so that the data is linked to the user_id (PK) then it should be fine. Alternatively you can setup a user_roles table which contains access rights.
As far as I know and how I have been programming, yes. If you are looking for extra security, perhaps check the user's password/salt against what is in the database.
l i need to do is make sure the queries pull only the data based off their unique id
I'm not sure what you mean by this, but it is too a general/broad statement to be either bad or good. It really depends on the system you're building. This is by no means a generally applicable statement.
Now in your current set-up this looks somewhat correct, but in the long-ish term you might need some data be public, or at least accessible by several people. This is impossible in your current design.
I would split the access and content, as they are separate things. Save what users (or look up a role-based pattern) have access to what data in separate tables, so you can build on what you have later, and add multiple user functionality.
This could become a long discussion, so I'll end with this: The bottomline with all database design is that you should save your information in a way that represents logical units, as it is in the real world (Yes, I'm taking some shortcuts here). So coupling a username to an id seems normal. But making the connection between a job and a user isn't that logical per se. A job can be visible to multiple users, no sweat. Or more then one user could have added the information. You could say that only 1 user is the 'owner' of a job or any other piece of data, but it seems too restrictive to make your access control purely out of who "owns" the data.
But then again, it is only a warning for the future. If you never need this, you don't.
You could have multiple databases, one per user. You'll need to have a way to do schema changes & upgrades though, like phinx. I wouldn't recommend this unless you foresee users having multiple users on their own account.
Related
Here I come again ;)
I am doing an application where each user will have their own DB.
Is it ok if I store session for each user in their individual DB? Or is it for some reason convenient to have active sessions in a common DB for all users?
Sorry about my question, I am kind of new to this level. :) I am working with PHP and MySQL, if that makes any difference, although I thik the question is language independent.
In a typical application, there will only be one database with several tables, where each table can have several records.
Sessions
You can just save sessions the same way you would add a record to database.
Profile Details / Friendship
This is where relationships take place.
Consider the image below. Credits to the owner on w3stack(dot)org.
Focus and try to study on the three tables above: Users, Friendships, Friends(virtual table). Ignore the virtual table concept for now, so you will not be much confused.
It is really a BAD, and I mean BAD approach to create individual databases for each users. What if you thought of adding a "following" and "follower" feature to your application? You would need to add another table, and re-add all those friends from another db. If UserA will have 100 friends with each database, you wouldn't want to query all those 100 databases.
To end, just use a single DB, and identify relationships according to your application features. It is important to plan your structure before you actually apply it on hands-on. Happy coding!
I've been working on a web application for a company that assists them with quoting, managing inventory, and running jobs. We believe the app will be useful to other companies in the industry, but there's no way I want to roll out separate instances of the app, so we're making it multi-user (or multi-company might be a better term, as each company has multiple users).
It's built in Codeigniter (wish I had've done it in Rails, too late now though), and I've tried to follow the skinny-controller fat-model approach. I just want to make sure I do the authorisation side of things properly. When a user logs in I'd store the companyID along with the userID in the session. I'm thinking that every table that the user interfaces with should have an additional companyID field (tables accessed indirectly via relationships probably wouldn't need to store the companyID too, tell me if I'm wrong though). Retrieving data seems pretty straight forward, just have an additional where clause in AR to add the company ID to the select, eg $this->db->where('companyID', $companyID). I'm ok with this.
However, what I'd like to know is how to ensure users can only modify data within their own company (in case they send say, a delete request to a random quoteID, using firebug or a similar tool). One way I thought of is to add the same where clause above to every update and delete method in the models as well. This would technically work, but I just wanted to know whether it's the correct way to go about doing it, or if anyone had any other ideas.
Another option would be to check to see if the user's company owned the record prior to modification, but that seems like a double-up on database requests, and I don't really know if there's any benefit to doing it this way.
I'm surprised I couldn't find an answer to this question, I must be searching for the wrong terms :p. But I would appreciate any answers on this topic.
Thanks in advance,
Christian
I'd say you're going about this the correct way. Keeping all of the items in the same tables will allow you to run global statistics as well as localized statistics - so I think this is the better way to go.
I would also say that it would be best to add the where clause you mention to each query (whether it's a get, update, delete. However, I'm not sure you'd want to manually go in and do that for all of your queries. I would suggest you overwrite those methods in your models to add the relevant where clauses. That way, when you call $this->model->get(), you will automatically get the where->($companyID, $userID) clause added to the query.
From the looks of things it looks like this might be a more API type system (as otherwise this is simply a normal user authentication system).
Simple Authentication
Anyway, the best bet I can see for an API is to have two tables, companies and users
in the companies table have an companyID, and password. in the users table link each user to a company.
Then when a user makes a request have them send through the companyID and password with every request.
oauth
The next option, slightly harder to implement, and means that the other end must also setup Oauth authentication is oauth.
But, in my opinion is much nicer overall to use and is a bit more secure.
One way to do it would be with table prefixes. However, if you have a lot of tables already, duplicating them will obviously grow the size of the db rapidly. If you don't have many tables, this should scale. You can set the prefix based on user credentials. See the prefixes section of this page: http://codeigniter.com/user_guide/database/queries.html for more on working with them.
Another option is to not roll out separate instances of the application, but use separate databases. Here is a post on CI forum discussing multiple db's: http://codeigniter.com/forums/viewthread/145901/ Here again you can select the proper db based on user credentials.
The only other option I see is the one you proposed where you add an identifier to the data designating ownership. This should work, but seems kinda scary.
I have built a web application for one user, but now I would like to offer it to many users (it's an application for photographer(s)).
Multiple databases problems
I first did this by creating an application for each user, but this has many problems, like:
Giving access to a new user can't be automated (or is very difficult) since I have to create a subdomain, a database, initial tables, copy code to a new location, etc. This is tedious to do by hand!
I can't as easily create reports and statistics of usage, like how many projects do my users have, how many photos, etc.
Single database problems
But having just one database for each users creates it's own problems in code:
Now I have to change the DB schema to accommodate extra users, like the projects table having a user_id column (the same goes for some other tables like settings, etc.).
I have to look at almost each line of code that accesses the database and edit the SQL for selecting and inserting, so that I sava data for that specific user, at the same time doing joins so that I check permissions (select ... from projects inner join project_users ... where user_id = ?).
If I forget to do that at one spot in the code it means security breach or another unpleasant thing (consider showing user's projects by just doing select * from projects like I used to do - it will show all users' projects).
Backup: backup is harder because there's more data for the whole database and if a user says: "hey, I made a mistake today, can you revert the DB to yesterday", I can't as easily do that.
A solution?
I have read multiple questions on stackoverflow and have decided that I should go the "single database" route. But I'd like to get rid of the problems, if it's possible.
So I was thinking if there was a way to segment my database somehow so that I don't get these nasty (sometimes invisible) bugs?
I can reprogram the DB access layer if needed, but I'm using SQLs and not OO getter and setter methods.
Any help would be greatly appreciated.
I don't think there's a silver bullet on this one - though there are some things you can do.
Firstly, you could have your new design use a different MySQL user, and deny that user "select" rights on tables that should only be accessed through joins with the "users" table. You can then create a view which joins the two tables together, and use that whenever you run "select" queries. This way, if you forget a query, it will fail spectacularly, instead of silently. You can of course also limit insert, update and delete in this way - though that's a lot harder with a view.
Edit
So, if your application currently connects as "web_user", you could revoke select access on the projects table from that user. Instead, you'd create a view "projects_for_users", and grant "select" permissions on that view to a new user - "photographer", perhaps. The new user should also not have select access to "projects".
You could then re-write the application's data access step by step, and you'd be sure that you'd caught every instance where your app selects projects, because it would explode when trying to retrieve data - neither of your users would have "select" permissions on the projects table.
As a little side bonus - the select permission is also required for updates with a where clause, so you'd also be able to find instances where the application updates the project table without having been rewritten.
Secondly, you want to think about the provisioning process - how will you grant access to the system to new users? Who does this? Again, by separating the database user who can insert records into "users", you can avoid stupid bugs where page in your system does more than you think it does. With this kind of system, there are usually several steps that make up the provisioning process. Make sure you separate out the privileges for those tasks from the regular user privileges.
Edit
Provisioning is the word for setting up a service for a new user (I think it comes from the telephony world, where phone companies will talk about provisioning a new service on an existing phone line). It usually includes a whole bunch of business processes - and each step in the process must succeed for the next one to start. So, in your app, you may need to set up a new user account, validate their email address, set up storage space etc. Each of those steps needs to be considered as a step in the process, not just a single task.
Finally, while you're doing this, you may as well think about different levels of privilege. Will your system merit different types of user? Photographers, who can upload work, reviewers who can't? If that's a possible feature extension, you may want to build support for that now, even if the only type of user you support on go-live is photographer.
Well, time to face some hard facts -- I think. The "single database problem" that you describe, is not a problem, but a normal (usual) design. Quite often, one is simply a special case of many.
For some reason you have designed a web-app for one user -- not many of those around.
So, time to re-design.
I have been creating a web app and am looking to expand. In my web app I have a table for users which includes privileges in order to track whether a user is an administrator, a very small table for a dynamic content section of a page, and a table for tracking "events" on the website.
Being not very experienced with web application creation, I'm not really sure about how professionals would create systems of databases and tables for a web application. In my web app, I plan to add further user settings for each member of the website and even a messaging system. I currently use PHP with a MySQL database that I query for all of my commands, but I would be willing to change any of this if necessary. What would be the best wat to track content such as messages that are interpersonal and also specific user settings for each user. Would I want to have multiple databases at any point? Would I want to have multiple tables for each user, perhaps? Any information on how this is done or should be done would be quite helpful.
I'm sorry about the broadness of the question, but I've been wanting to reform this web app since I feel that my ideas for table usage are not on par with those that experienced programmers have.
Here's my seemingly long, hopefully not too convoluted answer to your question. I think I've covered most, if not all of your queries.
For your web app, you could have a table of users called "Users", settings table called "UserSettings" or something equally as descriptive, and messages in "PrivateMessages" table. Then there could be child tables that store extra data that is required.
User security can be a tricky thing to design and implement. Do you want to do it by groups (if you plan on having many users, making it easier to manage their permissions), or just assign individually due to a small user base? For security alone, you'd end up with 4 tables:
Users
UserSettings
UserGroups
UserAssignedGroups
That way you can have user info, settings, groups they can be assigned to and what they ARE assigned to separated properly. This gives you a decent amount of flexibility and conforms to normalization standards (as mentioned above by DrSAR).
With your messages, don't store them with the username, but rather the User ID. For instance, in your PrivateMessages table, you would have a MessageID, SenderUserID, RecipientUserID, Subject, Body and DateSent to store the most basic info. That way, when a user wants to check their received messages, you can query the table saying:
SELECT * FROM PrivateMessages WHERE RecipientUserID = 123556
A list of tables for your messages could be as such:
PrivateMessages
MessageReplies
The PrivateMessages table can store the parent message, and then the MessageReplies table can store the subsequent replies. You could store it all in one table, but depending on traffic and possibly writing recursive functions to retrieve all messages and replies from one table, a two table approach would be simplest I feel.
If I were you, I'd sit down with a pencil and paper, and write down/draw what I want to track in my database. That way you can then draw links between what you want to store, and see how it will come together. It helps me when I'm trying to visualise things.
For the scope of your web app you don't need multiple databases. You do need, however, multiple tables to store your data efficiently.
For user settings, always use a separate table. You want your "main" users table as lean as possible, since it will be accessed (= searched) every time a user will try to log in. Store IDs, username, password (hashed, of course) and any other field that you need to access when authenticating. Put all the extra information in a separate table. That way your login will only query a smaller table and once the user is authenticated you can use its ID to get all other information from the secondary table(s).
Messages can be trickier because they're a bigger order of magnitude - you might have tens or hundreds for each user. You need to design you table structure based on your application's logic. A table for each user is clearly not a feasible solution, so go for a general messages table but implement procedures to keep it to a manageable size. An example would be "archiving" messages older than X days, which would move them to another table (which works well if your users aren't likely to access their old messages too often). But like I said, it depends on your application.
Good luck!
Along the lines of Cristian Radu's comments: you need to split your data into different tables. The lean user table will (in fact, should) have one unique ID per user. This (unique) key should be repeated in the secondary tables. It will then be called a foreign key. Obviously, you want a key that's unique. If your username can be guaranteed to be unique (i.e. you require user be identified by their email address), then you can use that. If user names are real names (e.g. Firstname Sirname), then you don't have that guarantee and you need to keep a userid which becomes your key. Similarly, the table containing your posts could (but doesn't have to) have a field with unique userids indicating who wrote it etc.
You might want to read a bit about database design and the concept of normalization: (http://dev.mysql.com/tech-resources/articles/intro-to-normalization.html) No need to get bogged down with the n-th form of normalization but it will help you at this stage where you need to figure out the database design.
Good luck and report back ;-)
Hey there guys and gals. I'm very new to php and am following various tutorials, reading books, watching videos etc.
The reason I'm learning is to create one specific web application, as well as to make that jump from simple geek to proper nerd, of course.
So far I've managed to learn most of what I need to create this web app.
The key part that has thus far eluded me is creating a dynamically-named, pre-defined(structure) database.
Essentially the application is a giant booking system. When a user registers I want the system to create a new database and link it to their account.
Whilst I know that I could easily have a php file that could run some SQL to create a database with all the right tables and columns, I don't know how to give that new database a unique name.
That name also needs to be written into the main users table so that whenever a user name connected to that client's account logs in, it uses that database name in the connection string and pulls up their data. Though, I'm sure that part wouldn't be as complicated.
If it matters, I'm using MySQL. Any help would be greatly-appreciated.
Edit: I should've made clear why I need more than one database in the first place, my apologies.
Essentially, it's going to be a private calendar(of sorts) system for businesses. Because of that, there will be an 'owner' of each database and all employees of that person will be utilising their employer's database.
If you need to create a new database for each user, I'd suggest radically rethinking your approach to the problem.
Very few problems require going that far.
For a booking system, for instance, I would imagine you would need one database with the following tables:
A user table with the user information for each user
A hotel table (if it's hotel booking, substitute what you need) with information on the hotels-
A booking table that links each booking to a user, a hotel and a time.
Edit:
An example of a problem for which it would be suited would be a meta-booking system; as in a system where you could set up a booking system for your own site or whatever.
If that is what you need, ignore this.
Find something unique about the user, like its username, and prefix the new database name with it. You can concatenate the number of databases already assigned to that user when creating a new one, so for example my first database would be inerte_0, my second one, inerte_1. Don't forget to sanitize whatever you'll use to prefix the database name to check if it's actually composed of allowed characters in Mysql's database names!
This is certainly possible. You could, for example, call uniqid() and then check for an existing database by that name in case you happen upon a duplicate (though that's unlikely).
However, I'm extremely wary of your overall approach. In general, you should not have to create tables (excluding TEMPORARY tables) at runtime. Instead, you could put data for all organizations in a single database, but with a simple column to distinguish which records are associated with which users.
It sounds like you're using a centralized database to store some of the information - the database wherein the "main users table" you mention resides. You also mention that you can identify which client a user is associated with, which implies a clients table in that centralized database.
That clients table very likely has a primary key field. There is your unique identifier for each client's database. You can use that, or you can generate a hash of some sort using a combination of information from that row, something like:
$unique = md5( $client_id . $client_name . $date_created );
You can also make sure that the column holding the client database names is set to be unique.