Tuple (computer science)

In computer science, the term tuple is used for ordered collections of values ​​(one-dimensional arrays ) and - especially in relational algebra - as a synonym for data set . Its values ​​are called attributes ( data field ).

The “ n tuple” or “tuple” for short denotes a collection with any number n of attributes.

The attributes are therefore the synonym for "fields". The term is sometimes used synonymously for "columns". Basically, however, this is not entirely correct, because a table column extends over the same field of 0 or more rows - that is, it forms a vector whose content is complex and therefore not atomic . A field always belongs to exactly one data record and therefore has atomic content.

In contrast to the list , the individual values ​​of a tuple cannot be changed while a program is running.

For clarification and as an analogy, Cantor's mathematical concept of sets is sometimes used . Unlike the tuple, this does not imply a specific order of its elements , a tuple does : its attributes (fields) must always appear in the same order.