Ordering

Sort Descending

Descending order puts larger keys first.

highlighted = computed this step

Sort descending

Descending order reverses the key direction so the largest key comes first.

largest first\text{largest first}

Reverse the score direction

The first score is now 30.

first score=30\text{first score}=30

Ordering examples are tiny finite table transforms; SQL dialects, NULL ordering, collations, indexes, optimizer behavior, performance, and product behavior are out of scope.

Sort descending: base tableSort descending: base tablesourceRowidkindscore01book3012game1023tool20 order byorder bycolumndirectionscoredesc sort keyssort keyssourceRowkey0[30]1[10]2[20] ordered rowsordered rowssourceRowidkindscore01book3023tool2012game10 page rowspage rowssourceRowidkindscore01book3023tool2012game10 tie groupstie groupskeysourceRowsnonenone order factsorder factsfactvaluerowCount3orderColumnCount1orderedRowCount3offset0limitnonepageRowCount3skippedBeforeCount0skippedAfterCount0unstableTiesnodeterministicTieOrdernot_needed

Same rows, new order

The base table stays the same; only the ordered output changes.

rows are reordered\text{rows are reordered}

Summary

Direction is part of the authored order specification.

ASC and DESC differ\text{ASC and DESC differ}