Thanks in advance.
Learning Drupal right now as recommended by many people and I cannot get a straight answer to this question:
What are the steps to setting up a CRUD application using Drupal?
(I'll explain further. But that is the premise.)
Working on an application that will do reporting and help out a small sales company with their prospecting and data analysis. Excel right? nope. Their clients will also be needing to access some of their data live via a webapp, so there will need to be different logins with levels of access (clients will see specific data related to their account, sales people will see their accounts, and management will see everything). Here's the real kicker they would like to eventually make it into a native app for android or IOS.
Originally I was going to build it in Codeigniter... which seemed easier, but it was recommended to me that I could cut down on my workload and utilized the "services" module later to do what I am looking to get done now and in the future.
Ignoring the project, I haven't even been able to figure out how to create a form for inputing data (I was assuming "Webforms"). Have that stored to a database, and then displayed in a sortable table.
I have searched around and can't really find a guide to building a simple CRUD application using Drupal as a CMS. I am totally willing to figure out how to put it together if someone could just tell me what modules/ things I need to do.
Example (INCORRECT)
1) Install these modules: Webform, views, CCK, Webform MySQL Views)
2) Activate the modules
3) Configure _ to interact with a specific database Table
4) Et Cetera
In all fairness, I'm still learning how to use Drupal and Doing CRUD (Create, Read, Update, Delete) type interactions might now be possible. If it isn't possible then I apologize for your reading all the way down.
Cheers + Happy Summer
Make sure you're using Drupal 7 (which has CCK built in). Then create one or more content types for the things people will see. Install Views and use that to build the displays for each role (Views is pretty powerful). You'll need to research which node access module would help you best restrict add/edit/delete privileges.
However, you said CodeIgniter is an option (ignoring the fact that CI is not maintained anymore). Any reason why Drupal was recommended instead of another PHP framework like Silex/Yii/Symfony/ZF2/LAravel? Depending on client needs (and how flexible they are) you may find yourself fighting against how Drupal wants to do certain things. If they eventually want to power more than a website via an API, seems like a non-Drupal solution could be better fit. (Until Drupal 8 is out and changes things up a bit)
Related
I want to create do the following things:
1. Create a new E-Commerce website
2. Update a already made website(superbrainacademy.com)
So the second thing, I have to include a log in provision so that some people which I authorize can get to see certain extra pages than others.
In e-commerce website I want everything like they can sign up themselves, I do not want to add each person manually, they log in with their email id and password and do shopping like something like flipkart.com. Well, payment gateway is out of scope for this question. What I need to know is how to start? In what language to make all this? Any guide on this?
What I know and i have created: I know programming in html and a little bit css. I make websites from downloading some good templates or just putting nice images at back and all. See my websites to have an idea(superbrainacademy.com or octindia.com)
I thought that maybe I could achieve this through joomla/drupal/wordpress. So I downloaded xampp and installed wordpress, drupal and joomla on it. The websites that open up look basic blogs to me (sorry but i am new to it) So I have no idea whether or not what I want can be accomplished by use of any of them. I also downloaded many many wordpress templates but they looked disgusting.
So what I need: A way to create a website with login id and password (signing in and signing up) but one has to be authorized by me as the users < 20 or so and the other needs to be done automatic as users > 100 or idk maybe greater. So how should i start.
Note: I do not prefer using automatic website making like weebly and all...
I would recommend using a CMS. If your willing to put some time into it you can learn to build your own template. I haven't used wordpress but I have built templates for Joomla, it takes some time to learn probably just as much time it would take to do what you want to do from scratch. Check out their guide to building a basic Joomla template.
http://docs.joomla.org/Creating_a_basic_Joomla!_template
So it seems that, you just need an e-commerce cms, and its likes of .
My suggestion for you is to deploy a Magento installation with a prebuilt template and demo just so you know where to start, and it gets easier for you to do stuff yourself, once you get a hang of it.
There are various of Magento/osCommerce template service providers out there some of them free maybe, some of them premium. Though I strongly bias my recommendation towards Magento than osCommerce, after myself having worked on both.
Note:- I am taking about opensource here, and mostly all of these cms installations tend to be quite similar.
Update:-
About integrating a login system inside your current website, you can use a script from HERE as per your requirement and complexity.
Joomla has inbuilt ACL:
http://docs.joomla.org/J3.2:Access_Control_List_Tutorial
so that would enable you to set specific access for specific user groups eg branches
It would allow you to either:
a) let people register individually
b) you approve each registration
c) you set up each user individually
You could also combine Joomla with an eCommerce component.
I find mixing Joomla with Mijoshop (OpenCart for Joomla) a good solution.
You can install Joomla with VirtualMart. If you don't need all functionalities of joomla just disable those from back-end. If you need a pure e-commerce site you can use OpenCart (lightweight solution) or Magento which is a much more complex e-commerce solution.
Update:
The second thing couldn't be accomplished by using HTML only. wardha-Web's answer below (php login) seems to be a good choice since it's quite simple. Another sophisticated way would be to modify your existing site and put it behind to a php framework where you can define access role based authentication, but for this you need to have some php and object oriented programming skills
I'm going to re-design and develop a new site for my client (they prefer wordpress as the new platform). They have got an existing big site with membership (with paypal), member portfolios and directories (with search) which are largely done manually in php associated with Silverstripe CMS.
I need some directions on how I best target this task with changing platforms from Silverstripe to Wordpress.
1) They want to keep their membership, directories data and migrate it to wordpress without members have to re-enter it again manually, is this possible, how can this be achieved?
2) For their membership, portfolios and directories, is it best to re-use the code, or is it too different between those two platforms? Or shall I search for some plugins to best match it and then manually add extra php code to match the existing site?
Which would be a better approach?
3) I've found some migrating companies who do migrations from Silverstripe to Wordpress with a cost, is the end product as logical as the original site? Or is it better to build it yourself in wordpress?
Anyone had experience of changing platforms, any suggestions are appreciated.
Thank you.
EDIT:
Sorry I've been away, thank you so much for your answers, Colyba, Cam and Zauberfisch, it is hard to choose one to be the answer. A little update, my client is more towards staying with Silverstripe after I used some of your knowledge, thank you.
Now I just found out they have got an offline Miscrosot Access to keep the membership details as well, my first thought was to just use the website and ditch MS Access, but their admin person has been using this MS Access for a long time even before the site was built, so I am just wondering is there anyway to synchronise both data?
I know the SS website membership database and MS Access membership database structures are set up differently, so I am just wondering is there any way to automatically update the offline MS Access membership when the SS website membership database is updated online? so they don't have to double add member details onto the offline MS Access. Any security issues? See question here, any suggestions are appreciated. Thank you very much!
I think what it comes down to is asking the client what the vision of the future or business direction is, also who will be responsible for maintaining the code base once the work is done?
I find WP has a lot of updates that need regular attention otherwise it is common to get hacked. If the client is aware of this and actions those that is good. Also does the business not have any intention of building further custom functionality other than what they currently offer to customers? if not, and the functionally is mostly commodity based stuff then sometimes WP can be the right tool for the job (even though you could do it in SilverStripe too).
However... if you are already on SilverStripe (perhaps an older 2.4 version) you could look at upgrading them to version 3 (assuming you are on 2.4) which has a much more user friendly admin interface (dare I say it more Wordpress-ish in layout) This might be more familiar to your client. If you do go this direction spend some time running your client through how to use the CMS as part of the project. I have found that helped me sell the benefits of SilverStripe when I was working as a freelancer.
SilverStripe will give you a great set of tools for future flexibility of the website (and the business). I usually feel pretty confident that when the business, say in a years time, asks for a very custom new feature to make their customers happy. I know that it can be easily built using SilverStripe's framework and made simple for CMS users to interact with that data through SilverStripe's extendable CMS interface. Also, of consideration is the licensing (we use BSD at SilverStripe), if strategically important and valuable code related intellectual property is being created, BSD allows retention of this while leveraging the SilverStripe platform. See http://www.silverstripe.org/bsd-license
So you can take more than just a technical approach in your discussions with a client.
There was this article which I quite liked http://www.chromatix.com.au/blog/wordpress-vs-silverstripe/ too.
Again, you will want to have a discussion with your client about the business plans going forward to ensure something gets put in place that can cater to those future needs. Sometimes if clients are not well educated about strategically thinking about their site it can lead to plugin bloat (just bolting on any shiny functionality without considering why) and ultimately their WP site falling over in the long term.
People are creatures of habit, they like to stick with what they know and what might have worked before... we just need to be careful not to extrapolate what used to work versus what will give you the flexibility to change in the future given we are in a very dynamic and chaotic business environment :) And particularly given that many IT systems being off the shelf commodities don't give a business any sustained competitive advantage (unique functionality and the capability to build very custom things to align with customer needs however is where business can better compete). If you and your competitor are both on WP you can both simply click a button and get the same features... how are you adding value for your customers if this is the case?
After all, value from information systems is realised through business objectives and making customers happy, and competing in business is about having something unique that others don't.
Hope my ramble helps in your decisions :) Granted I may be perceived as having a bias (after all I am the SilverStripe 'Community Awesomeness Manager' for full disclosure). When I was a freelancer, I have carried out projects in both WP and SS over the years, selecting the right tool for the job while considering the longer term needs of your clients is key. Does your client need a frozen microwave dinner or are they wanting to serve up some fresh home cooked goodness? Both can achieve the objective of being feed ;)
I fully agree with what colymba said in the comments.
what ever the reason may be, it is a bad idea to switch to WordPress with your type of content.
WordPress is a blog system, and its great at it, but doing custom stuff can quickly become rather painful.
Also, as cam pointed out, SilverStripe 3.x has great improvements over SilverStripe 2.x, so if you are still on 2.x, you should consider an update to SilverStripe 3 as alternative to WordPress (updating to SilverStripe also involves some work, as there have been many changes to how SilverStripe works, but its a lot less than migrating to another System)
Even though I strongly discourage your plan of action, I will still attempt to answer your questions (however I have not used WordPress for a complex Site, so I can't really speak to the internal workings of WordPress for this use case):
SilverStripe stores the passwords salted and hashed.
From what I can see WordPress does also salt and hash, but it looks slightly different, you might need to customize the WordPress password hasher to continue using the existing Passwords form SilverStripe.
All other Member data should be possible, just a matter of importing.
But it is for sure that you can't simply export and import your data, the schema of SilverStripe differs quiet a lot from WordPress, so you probably have to write your own import/data migrator.
Again, the architecture and data schema of SilverStripe is quiet different from the one of WordPress, so I am pretty sure you would need to rewrite the major part of your application.
Migration companies usually provide basic migration of standard data (Pages, Files and Users without any special features). your site seems to have a lot of custom features, and thus I am not sure if a company that offers migration will be what you are looking for here.
Plugins ... maybe you find one that does what you need. But the problem with WordPress plugins is that they usually do something, and if you want it slightly different, you are out of luck, so you might loose features that you previously had.
Also, a plugin (eg. for portfolio) does not solve your data migration problem.
overall, I would say its possible to do it.
However it will require advanced programming skills and a deeper understanding of how WordPress works internally.
So I recommend careful consideration before making a decision.
We have a dashboard that we'd like to build for our customers. This dashboard displays various statistics about one or more of their (business) Facebook Pages. The statistics are pulled from Facebook using their FQL and Graph APIs, stored locally in a MySQL database, and queried/derived/presented to the user based on dates requested and some other variables. Additionally, users will be able to take action on various items (e.g., reply to wall posts, etc.) using their JavaScript SDK.
One of the external developers we spoke with -- currently don't have any resources within the company with time to work on this -- has proposed building the system around Drupal. Now I'm a fan of CMS systems for web pages, blogs, etc. but using something like Drupal did not come to mind here as much of the functionality seems irrelevant.
Can someone please let me know the advantages and disadvantages of using Drupal for custom development work like this? While we're looking for an elegantly designed system that our developers (as we hire them) can maintain and extend over time, I'm not so sure a CMS is the way to go.
Thanks!
I wouldn't recommend Drupal at all for something like this. You don't really need a full-blown CMS like Drupal, and it would be pushing it to say you should use a framework such as CakePHP.
Personally, I would build this as a standalone app. I see no reason to get a framework involved unless you plan on expanding the APP considerably in the future.
Drupal is often called a content management framework because it's so extensible, and certainly you could implement the dashboard in Drupal. However, I would question the developer thoroughly about their rationale for using Drupal before consenting to it.
Everything you specified sounds like custom development and has nothing to do with content management. You're manipulating data from Facebook, not a database of content produced by an editor. Your data is custom data, not simple Drupal node data (title, body, etc). I would go with a general Web application framework such as CakePHP. That way you get templates and user authentication without all the CMS overhead.
While I don't think that Drupal is really necessary in this case, I think that the final decision lies with what the strengths of the contractors you are using are.
If Drupal will allow them to finish it more quickly, and more securely (due to the fact that Drupal will provide well test user authentication, used by many), then I would say let them go with Drupal.
That said, I do agree that Drupal sounds to be more than what is necessary, and there would probably be far less cruft if you used a simple framework.
The debate is that I need a PHP Framework/Drupal with the flexibility to add custom features to a potentially large application (web and with an api).
However, with a framework, like Kohana, I see myself tackling and re-inventing the wheel with the simple stuff like account management and cms stuff. Account management and quick data collection, like fast form creation, are tedious in Kohana but appear incredible simple in Drupal. On the other hand, based on my limited Drupal experience, I doubt building rapid custom "features" and allowing users to create "groups" and to manage their own roles within those groups is something Drupal can easily accomplish.
To simplify, is Drupal capable of true Web Applications; where the application is a service and provides custom results to each user? Can it provide a dashboard-like interface for users to change their settings or preferences? Can it aggregate data from particular users to provide better results/info to others?
If so, please point me to some knowledge :-)
I'll admit right away I'm a big fan of Drupal and I have never used Kohana, so this post will be one-sided.
In the company I work for they use Drupal or Zend Framework for pretty much all projects (Drupal being in the majority). Many ZF-oriented people dislike Drupal as it's structure is so far from the object oriented ZF-stuff, and Drupal is "just an CMS". As I see it Drupal is more of a Framework than "just" a CMS, and the best part being that it is incredibly flexible: everything is possible.
And yes there is indeed a module for everything. To be more specific:
On the other hand, based on my limited Drupal experience, I doubt building rapid custom >"features" and allowing users to create "groups" and to manage their own roles within >those groups is something Drupal can easily accomplish.
I can only guess what you mean with rapid custom features, but imo it's easy to expand Drupal with your own modules. Most features are available as (free, community contributed) modules, and many advanced looking features can be easily created for example with the "views" and "cck"-modules.
http://drupal.org/project/cck
http://drupal.org/project/views
Creating groups:
"organic_groups" ( http://drupal.org/project/og)
"og_user_roles" ( http://drupal.org/project/og_user_roles )
These modules together are what you need to create groups that have group spefic roles (and roles having specific rights). There are probably other ways than using "og_user_roles", but I'm advertising it because I've made a few patches for it a few years ago. The problem is usually a bit too many options.
If you want to extend group specific options you could code your own module, but most likely you don't need to because there already is a module for it. For example, there are at least 120 modules that integrate somehow with the "organic_groups"-module:
http://drupal.org/taxonomy/term/90?page=19
To simplify, is Drupal capable of true Web Applications; where the application is a >service and provides custom results to each user? Can it provide a dashboard-like >interface for users to change their settings or preferences? Can it aggregate data from >particular users to provide better results/info to others?
In short, yes. There are so many ways to achieve something you described. But probably they would involve at least the excellent "views"-module. I think of views as some kind of ultimate abstraction SQL layer and UI for anyone. And there are over 300 modules that somehow integrate with Views... ( http://drupal.org/taxonomy/term/89?page=55 )
This sounds that Drupal is all about the modules.. and I know some of my collegues even dislike it for that, because you never get to code fun stuff because it's already been done. At least you can look at the module code and learn from that. Or laugh at it, there's lots of badly programmed modules around too.
When you get to coding modules, you'll probably need lots of time to get used to the Drupal API, Forms API, Module hooks, the Theme override system, and the endless options from contrib modules. But it's worth the trouble.
I find this site very usefull to find a module for some specific need. The site shows the same module info as Drupal.org, but also user feedback/ratings, to find the best option:
http://drupalmodules.com/
If it's unclear, my answer would be go with Drupal :)
PS: D7 should be out very soon. Some might wait for it instead of starting with D6. During D5 people would wait a long time before upgrading to D6 because of missing modules. I believe for D7 the most important modules will be available for D7 very fast. Some research at the moment (04.12.2010):
About 190 modules promise to have a Drupal 7 version the day D7 is released:
http://drupal.org/project/modules?solrsort=sort_title%20asc&text=d7cx&display=table
About 130 modules are already available for D7 (most are included in the previous link):
http://drupal.org/project/modules?filters=drupal_core:103&solrsort=sort_title%20asc&text=d7cx&display=table
EDIT: As a newbie I'm only allowed to post one link, so, I removed http:// from the drupal.org-links
I worked with both Drupal and Kohana.
In my insight it really depends what you want to do. If you are going to make a web application that needs to grow a lot and should be flexible for it's growth then I recommend using Kohana. Kohana is made to keep your codebase clean and supporting in DRY (Don't Repeat Yourself). While it likely doesn't have as many modules as Drupal it does have some Auth and ACL modules.
If you want to be done fast and you don't mind making your application out of others their modules Drupal will get your work done fast. But keep in mind that when you are going to extend you will most likely run into problems that come from modules you don't know. Also it takes a bit flexibility from you.
Ultimately it's your choice. But I recommend using a MVC framework if you are going to write it from scratch.
There is no impossible thing to accomplish. The question is do you want to work with someone else code and try to figure out how to dig inside and extend so it can fit your needs or you want to go with a light framework like Kohana or maybe CodeIgniter(my personal favorite) and drive your own car, although you might need to "invent" some of the wheels.
Go ahead and research what plugins are there to your framework of choice as there are a lot of frameworks providing very good solutions which can provide you with these wheels.
In my personal opinion the time you will spend studying Drupal will be equivalent to the time needed for you to create your basic CMS functionality, but the nerves you will use dealing with stuff out of your control like the core Drupal code will shift the scales in favor of Framework.
The fun stuff about Drupal is what the community calls jokingly rule #35: there is a module for it. Unless you want to do something really tricky, you will often find that the functionality has already been implemented and you just need to configure it.
I am new to both Drupal (7.12) & Kohana (3.2.0)... My experience thus far is that Kohana's documentation SUCKS (or at least, what I've seen of it). And if their website and/or forum is written in Kohana, it sucks as well (slooooow, with overlapping fields, etc.). Whereas with Drupal, it has been clean and so far, very efficient (as best I can tell thus far).
I guess I'm wondering if the comments thus far were focusing on Drupal 6.x and haven't taken into consideration the more recent innovations in Drupal. Any thoughts/comments? Thanks.
As a newbie web developer, I can tell you that you need to analyze the use cases for your web application very strictly. If you are able to cover at least 75% of the use cases you foresee, that's a good start.
With that done, you need to figure if Drupal/Joomla/CMS(x) will give you all of that and with another potential unknown 5-10% feature creep. If so, you maybe better off getting in with Drupal etc.
Else, I think CodeIgniter or Symfony are great PHP frameworks to jump in with. Both offer solid tutorials, video and otherwise, and a helpful community. Kohana, which I am working on, I think you should get into if you really understand PHP and its flaws and realize that speed will be a critical factor. Those are the two big strengths that KO3 brings to the table and you should really need them to use it.
Hope this helps.
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I know ASP.NET C# very well. I make a lot of stuff like surveys and custom web applications.
I'm having a lot of trouble wrapping my head around Drupal and figuring out how to do 'special' programmatic things, like searching a list of clients, or creating a web application.
1 - I've been reading books and drupal API but I'm still having a lot of trouble getting started with anything at all. Where does custom code go in respect to pages, modules, snippets...? How do I replicate form X that I did in ASP.NET into a new page in drupal? Etc. It is super hard to wrap my head around Drupal, it seems so large and easy and extensible yet also like it is difficult for me to code. What can you recommend for an ASP.NET application programmer to learn to work with/in Drupal?
2 - Sometimes we write complete ASP.NET applications for clients, and these applications are not indended for clients to go editing them. For example, we will have our entire website in drupal, but inside of that website we will have a place for users to use a special search for database information. We don't want simple website editors and content providers trying to edit this specially coded page(s). How do I handle not wanting clients to edit anything in a Drupal application? Is it handled via page/user permissions? Is the best thing to develop and host an application completely outside of drupal? Is the drupal application it's own drupal instance inside of a drupal website (nested drupals?) ?
3 - Lastly, how do I handle databases? I understand Drupal and PHP are set to work best with MySQL. We have MS SQL databases that are used by multiple applications and would like to use them for new applications as we start using Drupal. For example, we have a Staff directory that feeds ASP.NET reporting application, ASP.NET Staff Listing application, and want to make a new Drupal PHP application that also uses (and perhaps inserts/updates more information into) that database. What is the best/easiest way to handle MS SQL databases and/or MySQL databases being used and updated by multiple Drupal and ASP.NET applications? Would it be easier to have all the applications use the MS SQL databases, or maybe to replicate the databases on MySQL for the Drupal/PHP apps and somehow sync the two databases?
I hope it is alright if I ask multiple related questions in a single post.
I'm afraid that I don't have any experience with Drupal so I can't offer any insights into your first or second questions, but on the third question:
What is the best/easiest way to handle
MS SQL databases and/or MySQL
databases being used and updated by
multiple Drupal and ASP.NET
applications?
If you are going to perform CRUD operations from both your ASP.NET applications and your PHP/Drupal applications, then I would recommend against trying to sync data back and forth between MySQL and MSSQL since this will cause latency problems plus you'll then have to deal with the differences between the two database management systems.
Instead, I would recommend that you look at using stored procedures to control all database accesses. This way you can ensure that all of your database CRUD operations conform to same rules and logic.
Using MSSQL in both ASP.NET and PHP shouldn't be a problem, especially not with the very excellent PDO library that provides a standard interface for accessing a number of popular database management systems. It should allow you to quickly and easily connect with and begin using your MSSQL databases within your PHP applications.
It is some good questions you ask. I'll try to answer them to the best of my ability. I haven't any experience with c# of APS.NET, so I don't know exactly where you are coming from. I myself learned Drupal as an inexperienced python/django developer. So in some ways I can understand some of the troubles you are going through trying to learn Drupal. Some of these things will simply require time/experience/experimenting before it will go away.
To really understand Drupal and the Drupal API you will first need a good understanding of PHP. Sometimes Drupal do some complex PHP things, so if you don't understand the syntax or the PHP functions etc, you can easy get lost.
Where do code live?
Drupal is built as a moduler system. Drupal itself is a set of modules, some of which are required for Drupal to work properly. If you want make some custom code, that is you want to do something, that you can't use a module for. There are about 5000 modules developed for Drupal. Often even when being a skilled programmer, the best choice is to find a module that will do what you need or can get you where close. So what you do, it to create a module of your own.
Make a folder with the name of the module
Create a modulename.info inside it which holds some info about the module formatted in a special way. Drupal will need it to fx display the module on the module list page where you activate modules.
Lastly create a modulename.module file where the core of your code for the module will be.
Another thing that is important to understand with Drupal, is that it uses a hook based system. Hooks are like events that fire once certain things happen that you want to hook into and either alter the flow, or do some things of your own. Fx you could record every time a specific form was displayed, or you could alter the form, adding/removing fields.
Forms
Drupal has a FAIP or Form API, that is uses to generate form, this is something that has it's own page in the documentation. The idea is that you create an associative PHP array which holds information about each element of the form, and Drupal will use that to create the form.
Books
There are a lot of good books for Drupal that you can learn from. The book I myself have learned the most from is Pro Drupal Development
First of all, Drupal has a very fine grained role based permission system, that will allow you to setup exactly what your clients are allowed to do. You can create different roles, like moderator, content creator, admin, sysadmin ect, and give different permissions to each role. This is pretty easy and is setup within the Drupal AI. However, you will need to know the permissions as some are super permissions that will give access to a lot of things. Now for integrating your applications, that is something that you probably want to write a custom module for. I don't know exactly how you want to do this. But I think the best result would be gotten by letting Drupal create the pages, forms etc from your application and just send data back and forth. That way the theme = layout of the site would be consistent. That way users wouldn't get the feeling that they left the site, but this simply was yet another feature the site offered.
Drupal is not just set to handle MYSQL best, You will actually need either MYSQL or PSQL as your drupal database backend. The reason is the way Drupal handles queries, that allow you to write non specific queries that will work, no matter on which of the two types you use, or if your tables has a prefix. So for all of the Drupal internals you will need one of the two. PHP can connect to MSSQL and run queries against that database, so you could without much problems write custom code that run queries to your other application's databases and either fetch or update data. Depending on the data, you might want to create a table in your database that you can read and write to, and then sync the databases when needed. It depends a bit on your use case. I have done the latter, in the case where I didn't need to write to the database, but only needed to fetch some product information form a legacy database that was still being used by other systems.
First of all, I think what's important to understand Drupal's limitations, there are things it's not really made for. It's sort of a web application framework but if you're doing a lot of custom work with your own custom datamodelling and stuff, Drupal might not be the most flexible or easily implementable solution to your kinds of problems. A more general framework like for instance Zend Framework might be more suited.
An important lesson in learning Drupal is: don't hack core or other modules. This will make upgrading core or modules very time-consuming. Instead "do like Drupal" and override using hooks. In theming you can also override with hooks, but also in other ways. Overriding is powerful so understand that concept well.
I'd say, pick a way of learning that is your style, screencasts, IRC, hacking, user meetups IRL, books, articles or any combination and look for material on Drupal. Just start mucking around and get a feeling and understanding of how Drupal works. Understanding the jargon is an important part, so what are: nodes, blocks, regions, hooks, modules, themes.
Drupal has a very flexible permission system, and it's probably the best choice to use that instead of making your own. You can write your own modules that add to or alter the behavior of Drupal. So if you want to write a new application that works with Drupal you can write a module performing the functionality the application has to have and make use of all the facilities Drupal offers, including users, the permission system, etc, etc. I don't really understand the last part of your second question "Is the drupal application it's own drupal instance inside of a drupal website (nested drupals?) ?". Drupal is a collection of PHP files on a server that, together with a slew of tables in a database serves request made to it. Multiple Drupal websites (so different PHP files) can reference the same database or parts of it (for example the user table). There's not really an "instance" of a Drupal site, as there's not really an "application". I could of course be too unfamiliar with these terms but I don't think PHP works with "instances" of "applications".
That's a hard problem, afaik Drupal doesn't work with MS SQL, so any connections in that direction you might have to make yourself. I'd also ask around the Drupal forums or on IRC.
Good luck!
rlb,
I've done quite a bit of Drupal and have strong ASP.NET experience. You really need to read up to get your mindset straight. They use layers in an MVC-like fashion that is very foreign to WebForms & ASP.NET MVC developers ... and quite frankly at first seems odd.
Here's a list of things I did to get really, really good quickly:
Get a host like at hostgator for $8 which will let you install Drupal
Get the book Pro Drupal Development for Beginners ... excellent and really covers a lot of areas http://www.amazon.com/Pro-Drupal-Development-Second-Beginning/dp/1430209895/ref=sr_1_2?ie=UTF8&s=books&qid=1257545528&sr=8-2
Get on the Drupal forums
Be ready to contribute. Drupal has a lot of features, but in the end the best way is to be someone who contributes code back
There are a number of IDEs to consider, but to start a text editor should be fine.
Good luck.
Some good answers here, so I'll just fill in some brief items.
1 - Learning Drupal: Pro Drupal Development is the best book for this. Getting into the issue queues and interacting with developers is a way to get familiar with specifics. Your question about forms relates to how Drupal handles forms. The FAPI is pretty robust in Drupal, and protects you from security gaffes. Also api dot Drupal dot org is where the code is documented, though there are docs elsewhere. Google is your friend. (On the Drupal site itself, use the native search to get faceted results.)
2 - This is a user permissions issue. You can limit creation and editing permissions based on content type. For access control (read), you will want to use one of the many modules for access control. It really depends upon your use case.
3 - Drupal has the most community support for MySQL, but people run Drupal on MS SQL as well. In Drupal 7, you will likely see much more support for non-MySQL as this release introduces database abstraction.
Probably the worst thing to do is hack around the margins. It really pays to learn the ins and outs of the Drupal basics -- administration and coding -- so that you can truly leverage the power Drupal brings to the table.
And if you're hunting for modules, http://drupalmodules.com is your friend. ;)