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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 ...
Unique constraints differ from primary key constraints in that they cannot be used to support referential constraints. Furthermore, the unique constraint columns may be set to null. Data type and data ...
Referential integrity (RI) is a method for ensuring the 'correctness' of data within a DBMS. People tend to oversimplify RI, stating that it is merely the identification of relationships between ...
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 ...