Control table

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Control tables are tables that control the control flow or play a major part in program control. There are no rigid rules about the structure or content of a control table—its qualifying attribute is its ability to direct control flow in some way through "execution" by a processor or interpreter. The design of such tables is sometimes referred to as table-driven design^[1][2] (although this typically refers to generating code automatically from external tables rather than direct run-time tables). In some cases, control tables can be specific implementations of finite-state-machine-based automata-based programming. If there are several hierarchical levels of control table they may behave in a manner equivalent to UML state machines^[3]

Control tables often have the equivalent of conditional expressions or function references embedded in them, usually implied by their relative column position in the association list. Control tables reduce the need for programming similar structures or program statements over and over again. The two-dimensional nature of most tables makes them easier to view and update than the one-dimensional nature of program code.

In some cases, non-programmers can be assigned to maintain the content of control tables. For example, if a user-entered search phrase contains a certain phrase, a URL (web address) can be assigned in a table that controls where the search user is taken. If the phrase contains "skirt", then the table can route the user to "www.shopping.example/catalogs/skirts", which is the skirts product catalog page. (The example URL doesn't work in practice). Marketing personnel may manage such a table instead of programmers.