A check constraint in a database is a rule that ensures that data meets a specific condition by restricting what data can be stored in a column. An example could be when creating a table in SQL ...

By using cascading referential integrity constraints, you can define the actions that SQL Server 2005 takes when a user tries to delete or update a key to which existing foreign keys point.

When I am working with an Oracle database, I still find myself using SQL*Plus for many quick and dirty database queries. In particular, I often look up constraints in SQL*Plus. In this post ...

SQL databases have constraints on data types and consistency. NoSQL does away with them for the sake of speed, flexibility, and scale. One of the most fundamental choices to make when developing ...