Ordering the Result Table
Strictly, the order of rows in a result table is undefined unless an ORDER BY clause is included in the SELECT statement.
Ascending or descending order may be specified; ascending order is the default.
Note: A SELECT statement without an ORDER BY clause may appear to give an ordered result in Mimer SQL, but you should include an ORDER BY clause if the ordering is important. A change in the database contents may otherwise change the order, particularly for a complex query where the order of execution is determined by the SQL optimizer.
ExampleSELECT * FROM formats ORDER BY format DESC;
Ordering by More than One Column
More than one column may be specified in the ORDER BY clause.
Example:SELECT * FROM formats ORDER BY category_id, display_order;
Ordering by Set Function or Computed Value
To order a result table by a set function or computed value, the column in the result table is given a label and the label is used in the ORDER BY clause.
Example:SELECT category_id, MAX(display_order) AS maximum_value FROM formats GROUP BY category_id ORDER BY maximum_value;
The following query is incorrect, since there is no DISPLAY_ORDER column in the result table by which to perform the ordering:SELECT category_id, MAX(display_order) FROM formats GROUP BY category_id ORDER BY display_order;
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