Data integrity

Data integrity protects data from being destroyed or changed by unauthorized persons, system operation or hardware failures (such as physical damage to a disk), programming errors, interruptions before a job is completed (such as a power failure), or interference from running applications at the same time (such as serialization problems).

• Concurrency
  Concurrency is the ability for multiple users to access and change data in the same table or view at the same time without risk of losing data integrity.
• Journaling
  The DB2^® UDB for iSeries™ journal support supplies an audit trail and forward and backward recovery.
• Commitment control
  The DB2^® UDB for iSeries™ commitment control support provides a means to process a group of database changes like update, insert, DDL, or delete operations as a single unit of work (transaction).
• Savepoints
  A savepoint is a named entity that represents the state of data and schemas at a particular point in time within a unit of work. You can create savepoints within a transaction. If the transaction rolls back, changes are undone back to the specified savepoint, rather than to the beginning of the transaction.
• Atomic operations
  When running under COMMIT(*CHG), COMMIT(*CS), or COMMIT(*ALL), all operations are guaranteed to be atomic.
• Constraints
  DB2^® UDB for iSeries™ supports unique, referential, and check constraints.
• Save/restore
  The i5/OS™ save/restore functions are used to save tables, views, indexes, journals, journal receivers, sequences, SQL packages, SQL procedures, SQL triggers, user-defined functions, user-defined types, and schemas on disk (save file) or to some external media (tape or diskette).
• Damage tolerance
  The server provides several mechanisms to reduce or eliminate damage caused by disk errors.
• Index recovery
  DB2^® UDB for iSeries™ supplies several functions to deal with index recovery.
• Catalog integrity
  Catalogs contain information about tables, views, SQL packages, sequences, indexes, procedures, functions, triggers, and parameters in a schema.
• User auxiliary storage pool (ASP)
  A schema can be created in a user ASP by using the ASP clause on the CREATE COLLECTION and CREATE SCHEMA statements.
• Independent auxiliary storage pool (IASP)
  Independent disk pools are used to set up user databases on the iSeries™ server.