Crafting Constraints with SSMS

Most of the articles that I presented so far for database development have been centered around the exact Microsoft T-SQL syntax to perform a certain operation. At the University of Rhode Island, I learnt how to program in Pascal before typing in my first ANSI SQL statement. In short, I will always be some type of developer in my heart. However, many people do not come from a computer science and math background. The SQL Server Management Studio (SSMS) has menus and dialog boxes to achieve many of the same…

Basic Training – Default Constraint

Today, I continuing my series of talks on fundamental SQL Server database topics. I am a proud United States Army Reservist (USAR) Veteran. Just like boot camp I went to so long ago, I am going nick name the series BASIC TRAINING. In my last article, I was talking about how to ADD, ALTER and DROP columns using the ALTER TABLE statement. One problem that we faced was how to add a column with a NOT NULL clause to an existing table that contained data. I will be introducing the…

Crafting Databases – Part 4

The ALTER TABLE statement is part of the Data Definition Language (DDL). The statement is used to modify a table after it has been created. Today, I would like to talk about the three integrity concerns that data modelers deal with. Integrity Concerns Entity Data Integrity – Adding primary keys to makes sure rows are unique. Referential Data Integrity – Adding foreign keys to make sure relationships are maintained. Domain Data Integrity – Creating constraints or triggers enforce the range of data values. Again, we will be working with the…