Downloaded from https://www.everyspec.com ADS-79D-HDBK is missing when a new row to be inserted does not contain a value for a non-NULL column that has no explicit DEFAULT clause in its definition. b. Primary Key Rules: Column (field) is identified for containing a ―primary key‖ value that is unique to each row (record). Data entries are disallowed for INSERTs and UPDATEs to rows (records) containing non-unique primary key fields. c. Relational Integrity Rules: A rule defined on a key (column or set of columns) in one table that guarantees that the values in that key match the values in a key in a related table (the reference value).
Referential integrity also includes the rules that dictate what types of data manipulation are allowed on referenced values and how these actions affect dependent values. An example of a referential integrity rule is ―Set to Default‖ where when referenced data is updated or deleted, all associated dependent data is set to a default value. d. Zero Rules: In strict mode, date entries do not permit '0000-00-00' as a valid date. Dates are disallowed where the year part is nonzero but the month or day part is 0 (for example, '0000-00-00' is legal but '2010-00-01' and '2010-01-00' are not). Check that the month is in the range from 1 to 12 and the day is in the range from 1 to 31.
Simple range checking does not apply to TIMESTAMP columns, which always require a valid date. Produce an error in strict mode (otherwise a warning) when a division by zero (or MOD(X,0)) occurs during an INSERT or UPDATE. A database trigger is an integrity enforcement rule that refers to a set of database procedures which are automatically invoked on INSERT, UPDATE, or DELETE query operations. Trigger functions performed by the DBMS serve to augment the input testing performed by the user interface of the application software. They are capable of performing more complex tests of the input fields in the course of a database transaction than a simple integrity constraint.
L.5.3 Data Computation. Data corruption and loss may occur during computation; therefore, the design should incorporate the necessary precautions to ensure that data is protected during data processing. Typically, integrity tests conducted as part of data processing involve the implementation of ―traps‖ within the application software for error and exception handling. These software traps will include tests for zero divide as well as the improper operator entry and input rejection due to the integrity constraints and database triggers in data acquisition.
Other value errors can include missing fields, out-of-bound entry values, ASCII dashes, hyphens, underscores, and disallowed characters involving backslashes, database functions (SELECT) used as column fields, and timestamp configurations. Computational data integrity tests will incorporate ―try‖ software blocks (or their syntactic equivalent, depending on software language) for accessing a relational database. In addition to trapping integrity tests, ―try‖ blocks ensure that data is not overwritten while being simultaneously accessed by multiple users in the ground station.
System-level computations that can be verified include compression algorithms (gzip), data and chunking algorithms (rsync, etc.). 229