TSQL - Is it possible to define the sort order?
Solution 1
It's incredibly clunky, but you can use a CASE statement for ordering:
SELECT * FROM Blah
ORDER BY CASE MyColumn
WHEN 'orange' THEN 1
WHEN 'apple' THEN 2
WHEN 'strawberry' THEN 3
END
Alternately, you can create a secondary table which contains the sort field and a sort order.
TargetValue SortOrder
orange 1
apple 2
strawberry 3
And join your table onto this new table.
Solution 2
Use a CASE statement:
ORDER BY CASE your_col
WHEN 'orange' THEN 1
WHEN 'apple' THEN 2
WHEN 'strawberry' THEN 3
END
Alternate syntax, with an ELSE:
ORDER BY CASE
WHEN your_col = 'orange' THEN 1
WHEN your_col = 'apple' THEN 2
WHEN your_col = 'strawberry' THEN 3
ELSE 4
END
Solution 3
If this is going to be a short-lived requirement, use a case statement. However, if you think it may be around for a while, and it's always going to be orange/apple/strawberry
order (or even if not - see below), you may want to think about sacrificing some disk space to gain some speed.
Create a new column in your table called or_ap_st
and use an insert/update trigger to populate it with the number 1, 2 or 3, depending on the the value of your fruit column. Then index on it.
Since the only time the data in that column will change is when the row changes, that's the best time to do it. The cost will then be incurred on a small number of writes rather than a large number of reads, hence amortised over the select
statements.
Your query will then be a blindingly fast:
select field1, field2 from table1
order by or_ap_st;
with no per-row functions killing the performance.
And, if you want other sort orders as well, well, that's why I called the column or_ap_st
. You can add as many other sorting columns as you need.
Solution 4
What I do in that case is
ORDER BY
CASE WHEN FRUIT = 'Orange' THEN 'A'
WHEN FRUIT = 'Apple' THEN 'B'
WHEN FRUIT = 'Strawberry' THEN 'C'
ELSE FRUIT
END
Solution 5
Going further from turtlepick's answer:
ORDER BY
CASE WHEN FRUIT = 'Orange' THEN 'A'
WHEN FRUIT = 'Apple' THEN 'B'
WHEN FRUIT = 'Strawberry' THEN 'C'
ELSE FRUIT
END
In case you have some more items in FRUIT and they happen to start with letters defined after THEN keywords, those items would appear within the hardcoded order. For example Banana shows up before Strawberry. You can circumvent it with
ORDER BY
CASE
WHEN FRUIT = 'Orange' THEN '.1'
WHEN FRUIT = 'Apple' THEN '.2'
WHEN FRUIT = 'Strawberry' THEN '.3'
ELSE FRUIT
END
Here I have used characters with lower ASCII values in hope that they would not appear at the beginning of values in FRUIT.
Comments
-
Justin808 over 4 years
Is it possible to define a sort order for the returned results?
I would like the sort order to be 'orange' 'apple' 'strawberry' not ascending or descending.
I know ORDER BY can do ASC or DESC but is there a DEFINED('orange', 'apple', 'strawberry') type thing?
This will be running on SQL Server 2000.
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paxdiablo over 13 yearsHah! Like I'm going to trust any SQL coming from someone called LittleBobbyTables :-)
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LittleBobbyTables - Au Revoir over 13 years@pax - <insert picture of Admiral Ackbar here> :-)
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Uzair over 8 yearsworked like a charm, I wish I could add 100 upvotes.
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user1451111 over 7 yearsWhat if i want certain items to appear on the end of the SELECT results ?
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user1451111 over 7 yearsWhat if i want certain items to appear on the end of the SELECT results ?
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user1451111 over 7 yearsWhat if i want certain items to appear on the end of the SELECT results ?
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beppe9000 almost 5 yearsyou can use a very high number or Z