Editing Join (SQL) (section)

===Join algorithms===
[[Image:Comparison of join algorithms.png|thumb|An illustration of properties of join algorithms. When performing a join between more than two relations on more than two attributes, binary join algorithms such as [[hash join]] operate over two relations at a time, and join them on all attributes in the join condition; [[Worst-case optimal join algorithm|worst-case optimal algorithms]] such as generic join operate on a single attribute at a time but join all the relations on this attribute.<ref>{{Cite arXiv |last1=Wang |first1=Yisu Remy |last2=Willsey |first2=Max |last3=Suciu |first3=Dan |date=2023-01-27 |title=Free Join: Unifying Worst-Case Optimal and Traditional Joins |class=cs.DB |eprint=2301.10841 }}</ref>]]
Three fundamental algorithms for performing a binary join operation exist: [[nested loop join]], [[sort-merge join]] and [[hash join]]. [[Worst-case optimal join algorithm]]s are asymptotically faster than binary join algorithms for joins between more than two relations in the [[worst case]].