Error validating database
In evaluating the basics of data validation, generalizations can be made regarding the different types of validation, according to the scope, complexity, and purpose of the various validation operations to be carried out.
For example: Data type validation is customarily carried out on one or more simple data fields.
Simple range and constraint validation may examine user input for consistency with a minimum/maximum range, or consistency with a test for evaluating a sequence of characters, such as one or more tests against regular expressions.
Code and cross-reference validation includes tests for data type validation, combined with one or more operations to verify that the user-supplied data is consistent with one or more external rules, requirements, or validity constraints relevant to a particular organization, context or set of underlying assumptions.
Structured validation allows for the combination of any of various basic data type validation steps, along with more complex processing.
There are a number of validation types that can be used to check the data that is being entered.
These additional validity constraints may involve cross-referencing supplied data with a known look-up table or directory information service such as LDAP.