Implementation

The implementation was based entirely on the programming tools Microsoft Access provides, i.e. Access Basic and SQL (Structured Query Language). A combination of both has proven to be most efficient.
SQL is a widely used database query language. It is set-based according to the descriptive paradigm, which describes the result set of a query. Due to the descriptive calculus SQL does not support the constructs belonging to the imperative paradigm, such as loops and "if-then" statements. Moreover, Access-SQL does not support many features of standard SQL (SQL-92), such as transaction, temporary tables, domains, assertions, and "case" expressions, etc.
Access Basic is a simple imperative language with some rudimentary object-oriented elements. In contrast to set-base database access with SQL, only record level access is supported by Access Basic. This requires more code and is often slower than a SQL-Query.

The functions of adding, editing and deleting a person consist of standard operations on a single table. Referential integrity (a person may only be deleted, if this person is not member of any team) is provided by the DBMS. Consequently, these functions do not have to be further considered. In contrast, the functions used for viewing, deleting, and creating person teams introduce considerable complications and are here discussed in full.


Definitions: Terminology, Data Structure Diagrams, Entity Relation Diagrams
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