Here is the normal mysql query
SELECT SUM( Minutes ) as minsDecPrac, COUNT( DISTINCT (CAST(dtDateTime as DATE))) as playDecPrac FROM `tbl_atschool_timelog` WHERE `intuid` = 48876 AND `intGametypeId` = 2 AND `intGame` = 1
Here is the Output
minsDecPrac playDecPrac
17 1
Here is the query using CASE WHEN
SELECT SUM(CASE WHEN intGametypeId = 2 AND intGame =1 THEN Minutes ELSE 0 END) AS minsDecPrac COUNT(DISTINCT CASE WHEN intGametypeId = 2 AND intGame =1 THEN (CAST(dtDateTime as DATE)) ELSE 0 END) AS playDecPrac FROM `tbl_atschool_timelog` WHERE `intuid` = 48876
Here is the Output
minsDecPrac playDecPrac
17 2
The problem is that if i use CASE WHEN, the output of "playDecPrac"(dtDateTime ) is wrong.
I don't know what i am wrong. Please help me if anybody knows
This clause here:
COUNT(DISTINCT CASE WHEN intGametypeId = 2 AND intGame =1 THEN (CAST(dtDateTime as DATE)) ELSE 0 END)
counts the 0 from ELSE 0 as a distinct value, in addition to the dates. So the COUNT(DISTINCT ) is one higher than it should be.
You might try ELSE NULL.
Related
I want to do math in a query, and was wondering if its better to do it in PHP or MYSQL.
Also, if I choose MYSQL can anyone help me with the query.
So far I have
SELECT COUNT(*) as total, booker, appdate,
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) book,
SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) tot
FROM appts WHERE WEEK(app_date)= WEEK(CURDATE()) GROUP BY booker
I want one more stat from this query.
I want to do book / (book+tot)
But obviously only if book!=0 or tot!=0, since obviously I don't want to divide anything by zero.
Is there a way to do this in a MYSQL query??
I want my output to be.....
book | 14
tot | 25
hold | 35%
Id also like to ORDER BY the hold percent from highest to lowest. Is this possible????
You can achieve what you ask for using a subquery, like this:
SELECT *, IF(book + tot, 100*book/(book + tot), NULL) AS hold
FROM (
SELECT COUNT(*) as total, booker, appdate,
SUM(status='DNS') book, SUM(status!='DNS') tot
FROM appts WHERE WEEK(app_date)= WEEK(CURDATE()) GROUP BY booker
) AS subquery
ORDER BY hold DESC
Note that in several places I'm using the fact that MySQL uses numbers for logical values. So you can sum up conditions without CASE, and you can write a formula for IF without <> 0 check.
Naive method:
SELECT
COUNT(*) as total,
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) book,
SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) tot,
IF( ( SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) +
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) ) = 0,
0,
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) /
( SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) +
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) )
) AS hold
FROM appts
WHERE WEEK(app_date) = WEEK(CURDATE()) GROUP BY booker
ORDER BY hold;
Or in order not to repeat your aliases, use a subquery:
SELECT *, IF (book + tot = 0, 0, book / (book + tot) * 100)
FROM (
SELECT
COUNT(*) as total,
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) book,
SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) tot,
FROM appts
WHERE WEEK(app_date) = WEEK(CURDATE()) GROUP BY booker
) AS subq
ORDER BY hold;
Or, more cleverly :) (book + tot = total)
SELECT *, IF (total = 0, 0, book / total * 100)
FROM (
SELECT
COUNT(*) as total,
SUM(CASE WHEN status='DNS' THEN 1 ELSE 0 END) book,
SUM(CASE WHEN status!='DNS' THEN 1 ELSE 0 END) tot,
FROM appts
WHERE WEEK(app_date) = WEEK(CURDATE()) GROUP BY booker
) AS subq
ORDER BY hold;
And, just for fun, the hackishly compactest form:
SELECT *, COALESCE(book / total * 100, 0) AS hold -- a division by 0 returns NULL
FROM (
SELECT
COUNT(*) total,
SUM(status='DNS') book, -- boolean "true" is internally integer "1"
SUM(status!='DNS') tot,
FROM appts
WHERE WEEK(app_date) = WEEK(CURDATE()) GROUP BY booker
) AS subq
ORDER BY hold;
$pos = select * from score_history where content_id = 6 && val = 1
$neg = select * from score_history where content_id = 6 && val = -1
i want to get the pos and neg scores in one query
but i dont want to use join
so perhaps some sort of IF/case statement ?
i've this but as you can guess it fails
SELECT count(*) as total ,
CASE
WHEN `val` = 1 THEN count(*) as `pos`
WHEN `val` = -1 THEN count(*) as `neg`
END
FROM score_history WHERE `content_id` = '46083' ";
is there any way to do this without using join or sub query ?
You can make use of the flexibility of MySQL to handle booleans and integers:
SELECT count(*) total, sum(val = 1) pos, sum(val = -1) neg
FROM score_history
WHERE content_id = '46083';
Whenever the condition is true it is a 1. Otherwise a 0. No CASE needed nor GROUP BY.
Close! A CASE statement doesn't return multiple columns, so you'll need 2 CASE statements and to wrap them in a SUM():
SELECT count(*) as total
,SUM(CASE WHEN `val` = 1 THEN 1 ELSE 0 END) as `pos`
,SUM(CASE WHEN `val` = -1 THEN 1 ELSE 0 END) as `neg`
FROM score_history WHERE `content_id` = '46083' ;
SELECT
SUM(CASE WHEN `val` = 1 THEN 1 ELSE O END) AS pos_count,
SUM(CASE WHEN `val` = -1 THEN 1 ELSE O END) AS neg_count
FROM score_history WHERE `content_id` = '46083';
Try this. Sorry I can't test, no database on this laptop.
select
count(*) as total,
sum(case val when 1 then 1 else 0 end) as pos,
sum(case val when -1 then 1 else 0 end) as neg
from score_history
where content_id = 6
Not sure if this is the best answer (and you would certainly want an index on your val column assuming there are many rows in the table) but this should certainly work - also assuming you only have 1 and -1 as values:
SELECT count(*), val from score_history where content_id = 6 group by val;
You were close; try the SUM function:
SELECT count(*) as total
, sum(CASE WHEN `val` = 1 THEN 1 ELSE 0 END) as `pos`
, sum(CASE WHEN `val` = -1 THEN 1 ELSE 0 END) as `neg`
FROM score_history
WHERE `content_id` = '46083';
select count(*)
from score_history
where content_id = 6 &&
(val = -1 or val=1)
group by val
I think this statement should work but I have tested on DBMS.
SELECT count(*) as total ,
count(case when val = 1 then 1 else null end) as pos,
count(case when val = -1 then 1 else null end) as neg
FROM score_history
WHERE `content_id` = '46083';
See SQLFIDDLE
Okay, a lot of these answers are close, but whenever you use an aggregate function you should use a group by.
SELECT count(*) as total
, (CASE WHEN `val` >= 0 THEN 'positive' ELSE 'negative' END) as interpreted_value
END
FROM score_history
WHERE `content_id` = '46083'
GROUP BY (CASE WHEN `val` >= 0 THEN 'positive' ELSE 'negative' END);
If you want to read up on how to use group by and aggregate functions here: https://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html
Is there a way to write a mysql select statement to run a count for a particular 1 field only, if greater than zero and equal to zero.
I could write 2 statements to achieve this but is it possible to do it in a single statement.
Something like this perhaps:
SELECT SUM(CASE WHEN x > 0 THEN 1 ELSE 0 END) as GreatherThanZero
, SUM(CASE WHEN x = 0 THEN 1 ELSE 0 END) as EqualZero
FROM table
WHERE x >= 0
Yes.
SELECT COUNT(*) FROM Table WHERE Field > 0
UNION SELECT COUNT(*) FROM Table WHERE Field = 0
Yes.
SELECT SUM(CASE WHEN column > 0 THEN column ELSE 0 END CASE), SUM(CASE WHEN column < 0 THEN column ELSE 0 END CASE) FROM mytable
Well, if I understood your question correctly, something like this should work:
SELECT
COUNT(Field)
FROM
Table
WHERE
Field >= 0
I want to fetch 2 coulmns count and do their total as a new column.
How can I do this?
i wrote this query, but this is returning wrong total.
SELECT count(case when `status`='1' then 1 else 0 end) AS HOT,
count(case when `status`='5' then 1 end)
AS Special_Case,count(case when 1=1 then 1 end) AS TOTAL
FROM `tbl_customer_conversation` group by
date(`dt_added`),user_id
COUNT will only give the times a record is matched, which in your query will always return 1. Because the values can either be 1 or 0. So count(1) is also 1 and count(0) is also 1.
AS, you want the total number of HOT cases and SPECIAL_CASE you have to use SUM.
SELECT
SUM(case when `status`='1' then 1 else 0 end) AS HOT,
SUM(case when `status`='5' then 1 end) AS Special_Case,
SUM(case when `status` = '1' or `status` = '5' then 1 end) AS TOTAL
FROM `tbl_customer_conversation`
group by date(`dt_added`),user_id
Simplified Table structure:
CREATE TABLE IF NOT EXISTS `hpa` (
`id` bigint(15) NOT NULL auto_increment,
`core` varchar(50) NOT NULL,
`hostname` varchar(50) NOT NULL,
`status` varchar(255) NOT NULL,
`entered_date` int(11) NOT NULL,
`active_date` int(11) NOT NULL,
PRIMARY KEY (`id`),
KEY `hostname` (`hostname`),
KEY `status` (`status`),
KEY `entered_date` (`entered_date`),
KEY `core` (`core`),
KEY `active_date` (`active_date`)
)
For this, I have the following SQL query which simply totals up all records with the defined status.
SELECT core,COUNT(hostname) AS hostname_count, MAX(active_date) AS last_active
FROM `hpa`
WHERE
status != 'OK' AND status != 'Repaired'
GROUP BY core
ORDER BY core
This query has been simplified to remove the INNER JOINS to unrelated data and extra columns that shouldn't affect the question.
MAX(active_date) is the same for all records of a particular day, and should always select the most recent day, or allow an offset from NOW(). (it's a UNIXTIME field)
I want both the count of: (status != 'OK' AND status != 'Repaired')
AND the inverse... count of: (status = 'OK' OR status = 'Repaired')
AND the first answer divided by the second, for 'percentage_dead' (Probably just as fast to do in post processing)
FOR the most recent day or an offset ( - 86400 for yesterday, etc..)
Table contains about 500k records and grows by about 5000 a day so a single SQL query as opposed to looping would be real nice..
I imagine some creative IF's could do this. You expertise is appreciated.
EDIT: I'm open to using a different SQL query for either todays data, or data from an offset.
EDIT: Query works, is fast enough, but I currently can't let the users sort on the percentage column (the one derived from bad and good counts). This is not a show stopper, but I allow them to sort on everything else. The ORDER BY of this:
SELECT h1.core, MAX(h1.entered_date) AS last_active,
SUM(CASE WHEN h1.status IN ('OK', 'Repaired') THEN 1 ELSE 0 END) AS good_host_count,
SUM(CASE WHEN h1.status IN ('OK', 'Repaired') THEN 0 ELSE 1 END) AS bad_host_count
FROM `hpa` h1
LEFT OUTER JOIN `hpa` h2 ON (h1.hostname = h2.hostname AND h1.active_date < h2.active_date)
WHERE h2.hostname IS NULL
GROUP BY h1.core
ORDER BY ( bad_host_count / ( bad_host_count + good_host_count ) ) DESC,h1.core
Gives me:
#1247 - Reference 'bad_host_count' not supported (reference to group function)
EDIT: Solved for a different section. The following works and allows me to ORDER BY percentage_dead
SELECT c.core, c.last_active,
SUM(CASE WHEN d.dead = 1 THEN 0 ELSE 1 END) AS good_host_count,
SUM(CASE WHEN d.dead = 1 THEN 1 ELSE 0 END) AS bad_host_count,
( SUM(CASE WHEN d.dead = 1 THEN 1 ELSE 0 END) * 100/
( (SUM(CASE WHEN d.dead = 1 THEN 0 ELSE 1 END) )+(SUM(CASE WHEN d.dead = 1 THEN 1 ELSE 0 END) ) ) ) AS percentage_dead
FROM `agent_cores` c
LEFT JOIN `dead_agents` d ON c.core = d.core
WHERE d.active = 1
GROUP BY c.core
ORDER BY percentage_dead
If I understand, you want to get a count of the status of OK vs. not OK hostnames, on the date of the last activity. Right? And then that should be grouped by core.
SELECT core, MAX(active_date)
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 1 ELSE 0 END) AS OK_host_count,
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 0 ELSE 1 END) AS broken_host_count
FROM `hpa` h1 LEFT OUTER JOIN `hpa` h2
ON (h1.hostname = h2.hostname AND h1.active_date < h2.active_date)
WHERE h2.hostname IS NULL
GROUP BY core
ORDER BY core;
This is a variation of the "greatest-n-per-group" problem that I see a lot in SQL questions on StackOverflow.
First want to choose only the rows that have the latest activity date per hostname, which we can do by doing an outer join for rows with the same hostname and a greater active_date. Where we find no such match, we already have the latest rows for each given hostname.
Then group by core and count the rows by status.
That's the solution for today's date (assuming no row has an active_date in the future). To restrict the result to rows N days ago, you have to restrict both tables.
SELECT core, MAX(active_date)
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 1 ELSE 0 END) AS OK_host_count,
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 0 ELSE 1 END) AS broken_host_count
FROM `hpa` h1 LEFT OUTER JOIN `hpa` h2
ON (h1.hostname = h2.hostname AND h1.active_date < h2.active_date
AND h2.active_date <= CURDATE() - INTERVAL 1 DAY)
WHERE h1.active_date <= CURDATE() - INTERVAL 1 DAY AND h2.hostname IS NULL
GROUP BY core
ORDER BY core;
Regarding the ratio between OK and broken hostnames, I'd recommend just calculating that in your PHP code. SQL doesn't allow you to reference column aliases in other select-list expressions, so you'd have to wrap the above as a subquery and that's more complex than it's worth in this case.
I forgot you said you're using a UNIX timestamp. Do something like this:
SELECT core, MAX(active_date)
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 1 ELSE 0 END) AS OK_host_count,
SUM(CASE WHEN status IN ('OK', 'Repaired') THEN 0 ELSE 1 END) AS broken_host_count
FROM `hpa` h1 LEFT OUTER JOIN `hpa` h2
ON (h1.hostname = h2.hostname AND h1.active_date < h2.active_date
AND h2.active_date <= UNIX_TIMESTAMP() - 86400)
WHERE h1.active_date <= UNIX_TIMESTAMP() - 86400 AND h2.hostname IS NULL
GROUP BY core
ORDER BY core;