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.