Suppose I have the following table:
id flag date
1 1 2012-01-01
2 1 2012-02-01
3 1 2012-03-01
4 0 2012-04-01
5 0 2012-05-01
6 0 2012-06-01
Is there anyway I can get maximum date for rows with flag as 1 and minimum date for row with flag as 0 using the same query?
Edited:
I want the result to looks something like this:
max min
2012-03-01 2012-04-01
Thank you.
You can try something like
SELECT MAX(CASE WHEN FLAG = 1 THEN Date ELSE NULL END) MaxFlag1,
MIN(CASE WHEN FLAG = 0 THEN Date ELSE NULL END) MinFlag0
FROM [Table]
try
select flag,
case when flag = 1 then max([date])
when flag = 0 then min([date])
end as date
from your_table
group by flag
You can use a UNION (ALL) to combine the results of two statements. The only restriction on those statements is that they both return the same amount and same type of columns.
Applied to your example, this would become
SELECT MAX(date) FROM YourTable WHERE flag = 1
UNION ALL SELECT MIN(date) FROM YourTable WHERE flag = 0
Related
I want to have a sum of a column that is based if the value of another column is this/that. Here's my table structure
id leave_hours leave_type overtime_hours employee_id
1 7.6 1 0 3
2 5 2 0 3
3 0 0 2.3 3
I have this query already but I need to have a column that will only sum if leave type is 1 and if the leave type is 2
SELECT employee_id, SUM(overtime_hours) AS ot_hrs, SUM(leave_hours if leave_type == 1) AS
leave_1, SUM(leave_hours if leave_type == 2) AS leave_2
FROM table
GROUP BY employee_id
Result should be:
employee_id ot_hrs leave_1 leave_2
3 2.3 7.6 5
Thanks for your inputs.
You need to use conditional aggregation to sum the different leave_hours separately:
SELECT employee_id,
SUM(overtime_hours) AS ot,
SUM(CASE WHEN leave_type = 1 THEN leave_hours ELSE 0 END) AS leave_1,
SUM(CASE WHEN leave_type = 2 THEN leave_hours ELSE 0 END) AS leave_2
FROM `table`
GROUP BY employee_id
Output:
employee_id ot leave_1 leave_2
3 2.3 7.6 5
Demo on dbfiddle
Note that if you use floating point numbers to store the hours, you may need to ROUND the results.
you can use max() with case when
SELECT employee_id,
max(overtime_hours) AS ot,
max(CASE WHEN leave_type = 1 THEN leave_hours END) AS leave_1,
max(CASE WHEN leave_type = 2 THEN leave_hours END) AS leave_2
FROM table_name
GROUP BY employee_id
output
employee_id ot leave_1 leave_2
3 2.3 7.599999904632568 5
I previously posted a question here: Mysql query with joined tables problems
but didn't get good answers, so I thought I break it down to show only the part that gives me a headache, I might get answers faster to this question, and if I can solve this, I can solve the previous problem too.
The values are referring to an item_id, and I want to get item_id's where the item is referring to (('good' OR 'bad') AND 'fast')
So item_id 1 must be listed, because it is good and also fast
item_id 2 should not listed because it is not fast.
The result i want to get
item_id
1
5
if I have a table like this
id item_id value
1 1 'good'
2 1 'fast'
3 2 'good'
4 2 'slow'
5 3 'good'
6 3 'slow'
7 4 'bad'
8 4 'slow'
9 5 'bad'
10 5 'fast'
11 6 'moderate'
12 6 'fast'
Can someone help me?
One way to see this is: you want a statement per item, so you aggregate and group by item. Criteria come in the HAVING clause.
select item_id
from mytable
group by item_id
having count(case when value = 'fast' then 1 end) >= 1
and count(case when value in ('good','bad') then 1 end) >= 1;
(You can also use sum(case when value = 'fast' then 1 else 0 end) >= 1 or max(case when value = 'fast' then 1 else 0 end) = 1 or some expression along those lines. COUNT(expression) counts expressions that are not null. As I am omitting an ELSE branch, a non-matching record results in null and is thus not counted. Some prefer SUM, some prefer COUNT - it's finally a matter of personal preference.)
One way to do this is with an EXISTS query.
Here's an example:
select t1.item_id
from your_table t1
where t1.value = 'fast'
and exists (
select NULL
from your_table t2
where t2.item_id = t1.item_id
and t2.value in ('good','bad')
);
Considering that a item can be good or bad, not both, I would use the simple way:
select item_id your_table
where value in ('good','bad','fast')
group by item_id
having count(*) = 2
count should be always 2 in those cases.
I want to count how many rows has given value (1) and count how many row has value(0)
id XXX 1 <== value 0 or 1
id YYY 1
id ZZZ 0
so the result would be
ones | zeros
2 | 0
thx in advance
Something like this should work:
select sum(case when value = 1 then 1 else 0 end) ones
, sum(case when value = 0 then 1 else 0 end) zeros
Try this
select sum(if(value=0,1,0)) as zeros,
sum(if(value=1,1,0)) as ones
from mytable
Let's say I have the following data.
id name_id completed
1 10 1
2 10 0
3 15 1
4 10 0
5 20 1
6 15 0
7 20 1
8 15 0
I'm trying to find a count by the name id, which is pretty simple
SELECT name_id, COUNT(*) FROM db
GROUP BY name_id
Now, I have a second component which I want to include in the query.
For name_id 10, I want to count just those values where completed is 1. For the other name_id's, I want to select them regardless of whether they are 0 or 1.
So I should end up with:
name_id count(*)
10 1
15 3
20 2
Name_id 10 only has a count of 1 because it's just the 1 which is completed, while the other counts include both 0 and 1.
Can anyone help with this task.
Thanks!
You can use a CASE expression inside of your aggregate function.
SELECT name_id,
sum(case
when name_id = 10
then case when completed = 1 then 1 else 0 end
else 1 end) Total
FROM db
GROUP BY name_id;
See SQL Fiddle with Demo.
Exclude the rows where name_id = 10 and completed = 0:
SELECT name_id, COUNT(*) FROM db
WHERE NOT (completed = 0 AND name_id = 10)
GROUP BY name_id
SELECT name_id, COUNT(*) FROM db
WHERE name_id != 10 or completed = 1
GROUP BY name_id
Count when name_id is not 10. If it is 10, count when completed = 1:
SELECT
name_id,
COUNT(CASE WHEN name_id <> 10 or completed = 1 THEN 1 END)
FROM db
GROUP BY name_id
My Data is
ID SCORE
1 55
1 -1
1 25
1 -1
1 -1
1 35
2 25
2 -1
2 65
2 55
2 21
2 -1
Now i want to add/sum the score of each id ignoring -1 and i am trying with this code which is not working
SELECT SUM(CASE when SCORE>-1 THEN SUM(SCORE) ELSE 0 END)
FROM jbit WHERE htno='$id'
Here i am already using WHERE so how can i use another WHERE, if i use multiple Where in single query it may effect other processes.. please help me out
Help me out friends
if there is only two column then there is no need to use SUM, you can try below
SELECT id, IF(SCORE=-1,0,SCORE) AS scoreSum
FROM table1
GROUP BY id
Working DEMO
alternative ( not tested )
SELECT id, SUM(IF(SCORE=-1,0,SCORE)) AS scoreSum
FROM table1
WHERE htno =$id
GROUP BY id
SELECT SUM(score) AS score_sum
FROM jbit
WHERE htno='$id'
AND score <> -1 ;
SELECT SUM(`SCORE`)
FROM `jbit`
WHERE `htno` = '$id'
`SCORE` > 0;
Though, I'd suggest you to change '$id' to just $id if the column type of htno is INTEGER.
SELECT SUM(score) FROM <tablename> WHERE score != -1