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 ...

Check Constraints are Supported in all Major DBMSs. 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 ...

Furthermore, the unique constraint columns may be set to null. Data type and data length are the most fundamental integrity constraints applied to data in the database. Simply by specifying the data ...

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 ...

Cascading referential integrity constraints are foreign key constraints that tell SQL Server to perform certain actions when a primary key field in a primary key-foreign key relationship is ...

An index is a database object that speeds data retrieval by directing the DBMS to the location in storage of a particular row for a given column. Indexes are usually created with the SQL statement ...