DATABASE LIMITATIONS DATABASE INTEGRITY

4-APP 2-2 Safety Management Manual SMM considered to be a database. Paper records can be maintained in a simple filing system i.e. a manual “database”, but such a system will suffice only for the smallest of operations. Storage, recording, recall and retrieval of data are cumbersome tasks. Safety data of whatever origin should preferably be stored in an electronic database that facilitates the retrieval of this information in a variety of formats. 3.2 The capability to manipulate, analyse and retrieve information in a variety of ways is known as database management. Most database management software packages incorporate the following organizational elements for defining a database: a Record. A grouping of information items that go together as a unit such as all data concerning one occurrence; b Field. Each separate information item in a record such as the date or location of an occurrence; and c File. A group of records having the same structure and an interrelationship such as all engine-related occurrences for a specific year. 3.3 Databases are considered to be “structured” when each data field has a fixed length, and its format type is clearly defined by a number, date, “yesno” answer, character or text. Often only a fixed choice of values is available to the user. These values are stored in reference files, often referred to as base tables or list value tables, for example, a selection of aircraft makes and models from a predetermined list. In order to facilitate quantitative analysis and systematic searches, free-form text entry in structured databases is minimized by confining it to a fixed field length. Often such information is categorized by a system of keywords. 3.4 Databases are considered to be “text-based” when information holdings are primarily written documents for example, accident and incident summaries or written correspondence. The data are indexed and stored in free-form text fields. Some databases contain large amounts of text and structured data; however, modern databases are much more than electronic filing cabinets.

4. DATABASE LIMITATIONS

There are limitations to be considered when developing, maintaining or using databases. Some of the limitations relate directly to the database system, while others relate to the usage of the data. If unsupportable conclusions and decisions are to be avoided, database users should understand these limitations. Database users should also know the purpose for which the database was assembled, and the credibility of the information entered by the organization which created and maintains it.

5. DATABASE INTEGRITY

5.1 Safety databases are a strategic element of an organization’s safety management activities. The data are vulnerable to corruption from many sources, and care must be taken to preserve the integrity of the data. Many employees may have access to the database for inputting data. Others will require access to the data for the performance of their safety duties. Access from multiple sites of a networked system can increase the vulnerability of the database. 5.2 The utility of a database will be compromised by inadequate attention to maintaining the data. Missing data, delays in inputting current data, inaccurate data entry, etc., corrupt the database. Even the application of the best analytical tools cannot compensate for bad data. Chapter 4. Hazards Appendix 2 4-APP 2-3 6. DATABASE MANAGEMENT Protection of safety data Given the potential for misuse of safety data that have been compiled strictly for the purpose of advancing aviation safety, database management must begin with protection of the data. Database managers must balance the need for data protection with that of making data accessible to those who can advance aviation safety. Protection considerations include: a adequacy of “access to information” laws vis-à-vis safety management requirements; b organization policies on the protection of safety data; c de-identification, by removing all details that might lead a third party to infer the identity of individuals for example, flight numbers, datestimes, locations and aircraft type; d security of information systems, data storage and communication networks; e limiting access to databases to those with a “need to know”; and f prohibitions on unauthorized use of data.

7. SAFETY DATABASE CAPABILITIES