Check constraints are supported in all of the major DBMS products, including DB2, Oracle, and SQL Server. But they are too-often ignored and not implemented in production databases. Properly defined, ...

Misconception Business-critical integrity constraints can protect only the quality of data, not enforce all business rules.

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, I ...

When a check constraint is defined, it places specific data value restrictions on the contents of a column through the specification of an expression explicitly defined in the table DDL and formulated ...

A new potential characteristic of a SAS data set known as integrity constraints has been added for SAS Version 7 or Version 8. Integrity constraints are a set of data validation rules that preserve ...