In my company we have a selected list of companies that are using our in-house built tool (e.g. Northwind).
When we make changes we deploy these to all our client locations.
The structure currently is: the application is installed at the client's location and the databases sit with them.
However, we would like to consolidate all this information into one database and clients will connect via web services for any data requests.
For example....We have deployed Northwind App and Db to company X, Y and Z and would like to create a single database to maintain all these company's data.
We have reviewed one option which is to create a field for the Company to associate it with the various tables and another option is to create a schema for each company and in this way we can allocate permissions to the relevant company. Is there an alternative to this and what are the pros and cons to the ways we could do this.
One con with adding a company field, is that we have to cater for indexes being the same in all the client databases and this makes it more difficult and the performance of the app as a whole due to multiple requests to the same db. Please Help?
Note: Using Sql Server 2008
Research "multi-tenant database architecture". (For your purposes, think of one tenant as one client.) You'll find a spectrum from "one database per tenant" to "every tenant in every table".
Read carefully. Writers in this field can confuse you. Expect technical terms like shared schema to mean different things to different writers.
See this SO answer for tradeoffs.
For your first step, I wouldn't consider anything besides simply moving those client databases in-house. Just doing that is going to give you and your application programmers enough headaches. You don't need an architectural change on top of it.
That will also give you time for research and testing.
Related
I have a client/server application currently that has a Oracle 10G database. The company that I purchased the application form is not providing support. The company when I purchased the application provided me a SQL tool with a READ Only access access to approx 30-40 views.
Based on my analysis the views provide some but not all the data and I want access to data which may be in other tables
I am not a developer but the business owner so excuse my naivety in some of the questions below.
Can I export/duplicate/replicate the Oracle DB to another Oracle DB and will a Oracle DBA be able to view/access all the tables and understand the relationships
What is the best way to create a duplicate DB that keeps in sync with the application DB which we currently have. We would like to use the Duplicate DB as a backend for a website.
Thanks a lot!
ML
Assuming that the Oracle database resides on a server in your organization, it seems premature to be talking about talking about replicating the data to a different database. It is certainly possible to do so. But you can also run many, many different applications against the same database. Unless you know that the current database server would not be able to cope with the additional workload of the new application or you are planning on investing the time and effort to transform the data into better data model as part of replicating the data (which is extremely unlikely if you don't already know what the underlying data model is and if you don't already know that this data model isn't going to work well for the new application), you probably want to start with the assumption that you can probably build the new application against the existing database.
A database developer or a DBA should be able (again, assuming that you own the server) to determine what underlying tables exist. That person should be able to at least get some idea of how the tables relate to each other based on the existing view definitions. If the original company did a good job building the database, a new developer/ DBA should have a relatively easy time understanding the relationships. If the original company did shoddy work or was intentionally secretive, it will be a more challenging undertaking.
first of all, I don't know if this is the right platform for this question. I hope it is. This is basically an architectural issue or more specifically a database design issue.
My company has asked me to create a service based website where individual subscribers can log in to their own customizable retail store. One fundamental question related to this requirement is designing the database. As I can understand there are two major approaches
Create a separate database based on a template for each subscriber / client.
Have a single database for all clients and link the tables based on primary key fields.
If any one has experience with the above scenario or can provide any useful insights, please do let me know.
Regards
Romi
separate database
You can put them easy to a other dedicated server
You have to administrate 1,000 databases for 1,000 clients
Your application need to figure out which database have to be used
one database with relationships
You have to administrate only one database
Less additional complexity in your application (tons of configurations etc.)
You can easy JOIN tables over all clients. For statistics or what ever.
We are working on an application in CakePHP that will be used by multiple companies. We want to ensure performance, scalability, code manageability and security for our application.
Our current beta version creates a new database for each customer. When a new company joins the site we run a SQL script to create a blank database.
This has the following advantages:
- Better security (companies users are separated from each other)
- We can set the database via the subdomain (IE: monkey.site.com, uses the site_monkey database)
- Single code base.
- Performance for SQL queries is generally quite good as data is split across smaller databases.
Now unfortunately this has many disadvantages
- Manageability: changes to database have to happen across all existing databases
- The SQL script method of creation is clunky and not as reliable as we would like
- We want to allow users to login from the home page (EG. www.site.com) but we cant currently do this as the subdomain determines what database to use.
- We would like a central place to keep metrics/customer usage.
So we are torn/undecided as to what is the best solution to our database structure for our application.
Currently we see three options:
- Keep multiple database design
- Merge all companies into one DB and identify each by a 'companyId'
- Some kind of split model, where certain tables are in a 'core database' and others are in a customer specific database.
Can you guys offer some of your precious advise on how you think we should best do this?
Any feedback / info would be greatly appreciated.
Many thanks,
kSeudo
Just my suggestion:
I think better you keep the customer related data in different databases and authentication related data in a common database So when a user logs in you should have an entry with domain that user belongs to and redirect to that domain and access the corresponding database and data.
Again your concern of changes to the database, You need to implement the changes in each databases separately. I think there is some advantages to this also. Some customers may ask for few changes according to their process. So this can be easily managed if you are keeping separate databases for different customers.
I'm creating a Multi-Tenant application that uses separate databases for each 'client'.
Is it safe to keep all the clients databases on one SQL server? Assuming I give each db its own user account?
Thanks
There was an excellent blog post by Brent Ozar last week on this exact subject.
How To Design Multi-Client Databases
Yes thats basically good idea to manage the tenanats from one sql server(better in terms of resources etc), but you need to create one seperate database for storing the connections strings of other tenant databases, roles etc.
It would be fine with one sql server, if you decide later on to place all the data into cloud. Basically its easy to manage . Also If you want to update any procedure, you can do it easily for all the tenants.
I'd normally use one database per client on the same instance.
From a security perspective, you then have only to deal with logins and users: not permissions per schema or whatever in one big database.
Note that SQL Server will balance resources across all database per instance fairly effectively: not all databases will be in use at the same time so memory etc will be allocated to need. You lose this advantage with multiple instances.
This is a repost of a question I asked 4 or 5 days ago, with zero response. Hoping for more luck this time...
(Using SQL Server 2008)
Within the next few weeks I plan to introduce SQL server to an office that is in dire need of a proper data server. Currently there is a heavy reliance on loose Excel and Access file (supplemented with frighteningly large amount of impenetrable VB code to do data manipulations) strewn all over the internal network.
We need SQL server for two things:
1. For internal databases that will be designed upfront and will be capturing data on an ongoing basis
2. For ad hoc uploads of datasets received from clients, which we then analyse
I am the only person in this office who is familiar with SQL. I will have to train the other 5 or 6 people to use it.
Now, my question is this: how would you guys set up the DBs so that it would be easy using Management Studio to visually recognize where what is being stored? To be more precise: if this were a windows file system it would look something like this:
c:\client work\client 1\piece of work 1 (db with 10 tables)\
c:\client work\client 1\piece of work 2 (db with 8 tables)\
c:\client work\client 1\piece of work 3 (db with 7 tables)\
c:\internal\accounting system\some db with 8 tables\
c:\internal\accounting system\some db with 5 tables\
c:\internal\some other system\some db with 7 tables\
etc.
So briefly, I need to visually split by internal and client work. Client work I need to split by different clients. For each client I need to split out the different distinct sets of work. (Internal work follows a similar pattern).
Solutions that I am aware of:
Run multiple data servers (e.g. one internal, one for client work). Not sure what the cons of this would be though
Assign schemas to tables
I would love to hear your suggestions!
Your organizational tools for managing SQL Server are instances, databases and schemas:
A server can run multiple instances. An instance is basically a completely separate server instance on the same machine.
An instance can manage multiple databases. The database is the standard boundary of integrity - you (usually) back up an entire database, referential integrity is constrained to being between objects in the same database, etc.
Each database can contain multiple schemas, which allow you to organize code.
All these "containers" relate to security in some way.
I recommend that you take an organization data and process inventory first, so that you understand what data you are dealing with, who uses it and how - with special attention on data which is public or collaborative (data used by certain people together) and which needs to be compartmentalized access (only used by a particular role). SQL Server is not really a great place of choice to be storing unstructured data - I would not view it as a simple replacement of a file server, for instance.
From there, proceed to define roles for your users. Having roles is a lot better strategy than assigning rights to individual users. It documents the semantic meaning of the access (any person performing this role needs this access as opposed to the user's identity - john and kate need access - this tells you nothing about why they need access). Be certain that the roles are sufficiently fine-grained. A departmental role like AccountsReceivable isn't nearly as useful as PaymentApprover or InvoiceProcessor or AccountsSupervisor. Users can act in multiple roles - this will give you a lot more self-documenting ability in your infrastructure and a lot fewer security holes and headaches.
This should help to define which containers you will need and what access to grant and guide your data infrastructure from there.
As far as giving users direct access, I'm with Randy Minder, SQL Server is only an expert user tool at best. If they are familiar with Access, a good option is to let them use Access against carefully designed and chosen views in SQL Server until they are ready for a more systematic data engineering approach.
IMO, users of your databases should not have to know or care where or how your databases are set up. And they shouldn't be given access to SSMS unless they are well trained in SQL. This is a disaster waiting to happen. You should be creating applications and/or reports that allow the user access to the data they need. That way they don't care where the data sits, and don't need to know.