Previously we considered the needs of Multi-tenant applications to maintain separation of data in the application and persistence. Separation by schema, vertical or horizontal partitioning, sharding or simple pointers techniques are possible techniques. Resource separation is also important in multi-tenant applications. Many of us have experienced sluggish performance of applications because a high-demand process is utilizing a majority of the […]

How do you test your applications? Believe it or not, you always test your software. There are companies that test their software through user affirmation; if they don’t get any complaints then the software must be correct. Hopefully this is not the normal testing methodology. You can test your software manually if it has a user interface or tools allowing […]

Most modern database software is based on the disk storage system of the operating system. There were some exceptions in the high end market for engines such as Sybase which had its own disk controller utilizing raw disks not accessible by the operating system. Recently Facebook released a new database into the Open Systems environment based on flash storage. The […]

Recently we talked about authentication as a central building block of a Multi-tenant application service. Another aspect of a Multi-tenant application architecture is the separation of data. Once we authenticate the credentials of the client, we must then assure they view only data to which they are entitled. Some data can be shared across tenants when it is common to […]

In SQL Server every batch has an attribute associated with it called Context_info. This session specific variable is accessible to the user to be set or read. Here is an example from BOL on setting and retrieving the value of Context_Info: SET CONTEXT_INFO 0x1256698456 GO SELECT CONTEXT_INFO() GO Some ingenious developers have determined this to be an effective way to […]

Today I was reading an article about “Architecting Multi-Tenant Applications in Windows Azure” in the June 13 edition of MSDN magazine. There were four areas the author intends to cover in the series where Azure helps in the design of applications. The first one was about Authentication. It turns out that Microsoft Azure Active Directory has some neat integration wrapped […]

Mark writes: I’m glad you bring some attention to application responsiveness, as I have often been on the raw end of poorly performing interfaces. Of course in client/server scenarios on the desktop this is often thread related, but I find this all to often over looked in the web application domain also, particularly where AJAX is concerned. I include two […]

Application Responsiveness In the Microsoft world, application responsiveness had always required a lot of effort until the later releases of the Dot Net Framework. A good example of application responsiveness would be the ability to click on a button in a form and have that fire off an action while still handling actions against that form. In other words, the […]

Private Cloud? Public Cloud? Hybrid? There are reports that some are abandoning plans to move to the public cloud, and we’ve been working with many different people putting together their own plans for the cloud. In the work we’ve been involved with, we’re seeing bigger plans for the public cloud as tools and technologies mature. While security concerns have been […]

Database Dependencies Database Dependencies occur when an object in a database will fail to function as defined when another object is modified or removed. For example, a View that is based on a table is dependent on the definition of that table. If the table is modified or deleted then the view will no longer continue to perform as designed. […]