Editing Surrogate key (section)

===Performance===

Surrogate keys tend to be a compact data type, such as a four-byte integer. This allows the database to query the single key column faster than it could multiple columns (which are often text - which is slower still). Furthermore, a non-redundant distribution of keys causes the resulting [[b-tree]] index to be completely balanced. Surrogate keys are also less expensive to join (fewer columns to compare) than [[compound key]].