This database was designed for time and attendance application.
I decided to move some part of business logic on DB side. This logic was implemented using triggers, stored procedures and views.
I use ErWin to design and constantly update DB model within the whole project live cycle. All model changes are written as SQL scripts that I apply to testing and production server when new version is issued.
I design DB such way that even there are big changes they do not lead to DB refactoring, so it has flexible and expendable structure.
DBMS: MS SQL 2008
This simple database was designed using MS SQL 2012 and used for contest web site.
Interesting thing that I incorporated into this DB was a durability for high loading. Our site process over 1mln requests per day when contests run.
It has very simple structure but table fields, indexes and views were optimized for high loading.
MS SQL 2010.
Total records: 100mln
I develop this database when was a student by dean request.
This DB keeps 100,000 student phones of our university. I used standard composition and decomposition rules to design well-optimized DB for quick search.
I decided to duplicate some fields to exclude extra joins and save performance.
It was developed for MySQL. I used paper and MySQL Workbench to design the model.
This DB has been used for last 7 years in my university.
This database was developed for custom CRM system.
The main idea was to save not standardized information about different objects, but also it must support transactions for orders/invoices.
I decided to use two DB: Mongo for keeping mixing object data and MS SQL for transitioning operations.
I got flexibility to save any fields, objects easy and quickly using Mongo that removes many restrictions, which the development team had before me.
I like analyzing and finding effective solutions for projects. I saw many situations when dev teams started projects without thing about future and then stuck.
Now DBs have over 20mln records which describes almost 100,000 business.
My next step is to implement OLAP for building different kind of stats on fly.