Reputation: 4161
Say I had a MySQL query like this:
SELECT id,
something,
CASE colour
WHEN 1 THEN 'not ripe'
WHEN 2 THEN 'ripe'
ELSE 'rotten'
END AS 'ripeness'
FROM fruit
WHERE fruit_type = 'apple'
If I wrapped the CASE
in parenthesis because I find it more readable:
SELECT id,
something,
(CASE colour
WHEN 1 THEN 'not ripe'
WHEN 2 THEN 'ripe'
ELSE 'rotten'
END) AS 'ripeness'
FROM fruit
WHERE fruit_type = 'apple'
Would that have a performance impact on the query?
Upvotes: 1
Views: 345
Reputation: 2016
don't think so, only time difference should be the compiler to decode your parenthesis,they will be compiled into same binary.
You can run a big data test to find out.
Upvotes: 1
Reputation: 310993
Both these queries are semantically equivalent. There shouldn't be any noticeable performance impact on using or not using parenthesis.
Upvotes: 2