


How to Prioritize Specific Field Values When Ordering Database Results in MySQL?
MySQL database result sorting: prioritize specific field values
In database table operations, it is a common requirement to prioritize records with specific field values. For example, consider a table with the following columns and data:
id | name | priority |
---|---|---|
1 | core | 10 |
2 | core | 9 |
3 | other | 8 |
4 | board | 7 |
5 | board | 6 |
6 | core | 4 |
The task is to reorder the results based on the priority
field, but giving priority to rows where name
is equal to "core". The desired output is as follows:
id | name | priority |
---|---|---|
6 | core | 4 |
2 | core | 9 |
1 | core | 10 |
5 | board | 6 |
4 | board | 7 |
3 | other | 8 |
In MySQL, this sorting can be achieved using the FIELD()
function. Here are some ways:
Fully sort all values:
SELECT id, name, priority FROM mytable ORDER BY FIELD(name, "core", "board", "other");
This query will sort the results according to the order specified in the FIELD()
function, giving priority to those values that appear first.
Only "core" will be prioritized:
SELECT id, name, priority FROM mytable ORDER BY FIELD(name, "core") DESC;
This query prioritizes rows where DESC
is equal to "core" by using name
, regardless of their other field values.
Preserves the sort order of other values:
SELECT id, name, priority FROM mytable ORDER BY FIELD(name, "core") DESC, priority;
This query prioritizes the "core" rows first using FIELD()
and then sorts the remaining rows in normal priority
order.
It is important to note that the FIELD()
function returns the one-based index of the matching value, or zero if the value is not found. Therefore, DESC
needs to be used unless all possible values are specified.
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