I have a table with columns: id and created(datetime)
id created
6 2011-11-04 20:32:09.673
5 2011-11-04 20:32:09.673
4 2011-11-04 20:29:55.000
3 2011-11-04 20:29:55.000
How to write sql, that will return counts of records that haven't, have 2 or have more than 2 equal creation dates. It can be 3 separate sqls.
Thank you
If I understand your question correctly, I believe this should do the trick, returning any creation dates that occur more than once.
This one will get those with more than 2.
SELECT
created
,COUNT(*) as [occurrences]
FROM
tableName
GROUP BY
created HAVING COUNT(*) > 2
Swap the > 2 for an = 2 to get those with 2 exactly and =1 to get those with only 1 occurrence.
Try:
select case reccount
when 1 then 'No matches'
when 2 then 'Exactly 2 matches'
else 'More than 2 matches'
end as number_of_matches,
count(*) as distinct_dates,
sum(reccount) as record_count
from (select created,
count(*) reccount
from mytable
group by created) v
group by
case reccount
when 1 then 'No matches'
when 2 then 'Exactly 2 matches'
else 'More than 2 matches'
end
Related
I am pretty new to postgresql (or sql), and have not learned how to deal with such "within group" operation. My data is like this:
p_id number
97313 4
97315 10
97315 10
97325 0
97325 15
97326 4
97335 0
97338 0
97338 1
97338 2
97344 5
97345 14
97349 0
97349 5
p_id is not unique and can be viewed as a grouping variable. I would like to change the number within each p_id to achieve such operation:
if for a given p_id, one of the value is 0, but any of the other "number" for that pid is >2, then set the 0 value as NULL. Like the "p_id" 97325, there are "0" and "15" associated with it. I will replace the 0 by NULL, and keep the other 15 unchanged.
But for p_id 97338, the three rows associated with it have number "0" "1" "2", therefore I do not replace the 0 by NULL.
The final data should be like:
p_id number
97313 4
97315 10
97315 10
97325 NULL
97325 15
97326 4
97335 0
97338 0
97338 1
97338 2
97344 5
97345 14
97349 NULL
97349 5
Thank you very much for the help!
A CASE in a COUNT OVER in a CASE:
SELECT
p_id,
(CASE
WHEN number = 0 AND COUNT(CASE WHEN number > 2 THEN number END) OVER (PARTITION BY p_id) > 0
THEN NULL
ELSE number
END) AS number
FROM yourtable
Test it here on rextester.
Works for PostgreSQL 10:
SELECT p_id, CASE WHEN number = 0 AND maxnum > 2 AND counts >= 2 THEN NULL ELSE number END AS number
FROM
(
SELECT a.p_id AS p_id, a.number AS number, b.maxnum AS maxnum, b.counts AS counts
FROM trans a
LEFT JOIN
(
SELECT p_id, MAX(number) AS maxnum, COUNT(1) AS counts
FROM trans
GROUP BY p_id
) b
ON a.p_id = b.p_id
) a1
use case when
select p_id,
case when p_id>2 and number=0 then null else number end as number
from yourtable
http://sqlfiddle.com/#!17/898c3/1
I would express this as:
SELECT p_id,
(CASE WHEN number <> 0 OR MAX(number) OVER (PARTITION BY p_id) <= 2
THEN number
END) as number
FROM t;
If the fate of a record depends on the existence of other records within (the same or another) table, you could use EXISTS(...) :
UPDATE ztable zt
SET number = NULL
WHERE zt.number = 0
AND EXISTS ( SELECT *
FROM ztable x
WHERE x.p_id = zt.p_id
AND x.number > 2
);
I have re-written this query about 20 times today and I keep getting close but no dice... I'm sure this is easy-peasy for y'all, but my SQL (Oracle) is pretty rusty.
Here's what I need:
PersonID Count1 Count2 Count3 Count4
1 0 0 2 1
2 1 1 1 0
3 1 1 1 2
Data is coming from several sources. I have a table People, and a table Values. People can have any number of values in that table.
PersonID Item Value
1 Check1 3
1 Check2 3
1 Check3 4
2 Check4 2
2 Check5 3
2 Check6 1
.. etc
So the query would, for each PersonID, count how many times the particular Value appears. The values are always 1, 2, 3, or 4. I tried to do 4 subqueries, but it wouldn't read the PersonID from the main query and just returned the count of all instances of value=1.
I was then thinking do a Group_By ... I don't know. Any help is appreciated!
ETA: I've deleted & re-written the query many times in many ways and unfortunately did not save any intermediate attempts. I didn't include it originally because I was in the middle of rearranging it again, and it's not runnable as-is. But here it is as it stands now:
/*sources are the tested requirements
values are the scores people received on the tested sources
people are those who were tested on the requirements */
WITH sub_query4 (
SELECT values.personid,
count (values.ID) as count4 --how many 4s
FROM values
INNER JOIN sources ON values.valueid = sources.sourceid
INNER JOIN people ON people.personid = values.personid
WHERE values.yearid = 2017
AND values.quarter = 'Q1'
AND instr (sources.identifier, 'TESTBANK.01', 1 ,1) > 0
AND values.value = '4'
GROUP_BY people.personid
)
SELECT p.first_name,
p.last_name,
p.position,
p.email,
p.locationid,
sub_query4.count4 as count4 --eventually this would repeat for 1, 2, & 3
FROM people p
WHERE p.locationid=406
AND p.position in (9,10);
values is a bad name for a table because it is a SQL keyword.
In any case, conditional aggregation should work:
select personid,
sum(case when value = 1 then 1 else 0 end) as cnt_1,
sum(case when value = 2 then 1 else 0 end) as cnt_2,
sum(case when value = 3 then 1 else 0 end) as cnt_3,
sum(case when value = 4 then 1 else 0 end) as cnt_4
from values
group by personid;
I prefer to use PIVOT for this. Here is Example SQL Fiddle
SELECT "PersonID", val1,val2,val3,val4 FROM
(
SELECT "PersonID", "Value" from VALS
)
PIVOT
(
count("Value")
FOR "Value" IN (1 as val1, 2 as val2, 3 as val3, 4 as val4)
);
I have to check certain rows from table and check if-else condition for each rows
TABLE: report
COLUMNS :
sl.no, count, total_count, calls
Sample Data:
sl.no count total_count calls
----------- ----------- ----------- -----------
1 2 6 4
2 2 7 5
3 4 9 3
Here i have to check if condition
if total_count > 6
select 'Y
else
select 'N'
I get correct answer for single row. If there is multiple row it can't check all, it check only last row of my table.
Use CASE expression
SELECT
*,
CASE WHEN total_count > 6 THEN 'Yes' ELSE 'N' END
FROM report
You must use CASE.It work like if-else in t-SQL. MSDN
For example:
SELECT [num],[count], [total_count], [calls], CASE WHEN [total_count] > 6 THEN 'Y' ELSE 'N' END FROM t
You could use CASE. You can read documentation.
SELECT *,
CASE WHEN total_count > 6 THEN 'Y' ELSE ' N' END
FROM Report
The SQL version of "inline if" is CASE:
SELECT
*,
CASE WHEN total_count > 6 THEN 'Y'
ELSE 'N'
END AS IsTotalCountGreaterThanSix
FROM YourTable;
This is table structure
id
1
2
3
4
5
6
I need result like this
id even odd
1 0 1
2 1 0
3 0 1
4 1 0
5 0 1
6 1 0
I tried
select id %2=0 then 1 else 0 end or id%2 <>0 then 1 else 0 odd
from table
How about
select
id,
~id & 1,
id & 1
from t
Take a look at the CASE keyword. It works very similarly to what you're trying to do in your SELECT statement. In addition, if you want to select multiple columns, separate them with a comma. The OR keyword is used for combining logical conditions in your query, not for specifying multiple columns.
An example of how you could use CASE in your query would be as follows:
SELECT id,
CASE WHEN id %2=0 THEN 1 ELSE 0 END AS Even,
[column2]
FROM [TableName]
The table structure is just Id?
you could try this!
select *,
case when id %2=0 then 1 else 0 end as even,
case when id %2 <>0 then 1 else 0 end as odd
from table
You have the right idea, but your syntax is a bit off. I'd use a CASE statement to create the even column, and then a calculate odd accordingly:
SELECT id, even, ABS(even - 1) AS odd
FROM (SELECT id, CASE WHEN id % 2 = 0 THEN 1 ELSE 0 END AS even
FROM my_table)
Quick one,
I have a table, with the following structure
id lid taken
1 1 0
1 1 0
1 1 1
1 1 1
1 2 1
Pretty simply so far right?
I need to query the taken/available from the lid of 1, which should return
taken available
2 2
I know I can simply do two counts and join them, but is there a more proficient way of doing this rather than two separate queries?
I was looking at the following type of format, but I can not for the life of me get it executed in SQL...
SELECT
COUNT(case taken=1) AS taken,
COUNT(case taken=0) AS available FROM table
WHERE
lid=1
Thank you SO much.
You can do this:
SELECT taken, COUNT(*) AS count
FROM table
WHERE lid = 1
GROUP BY taken
This will return two rows:
taken count
0 2
1 2
Each count corresponds to how many times that particular taken value was seen.
Your query is correct just needs juggling a bit:
SELECT
SUM(case taken WHEN 1 THEN 1 ELSE 0 END) AS taken,
SUM(case taken WHEN 1 THEN 0 ELSE 1 END) AS available FROM table
WHERE
lid=1
Alternatively you could do:
SELECT
SUM(taken) AS taken,
COUNT(id) - SUM(taken) AS available
FROM table
WHERE
lid=1
SELECT
SUM(case WHEN taken=1 THEN 1 ELSE 0 END) AS taken,
SUM(case WHEN taken=0 THEN 1 ELSE 0 END) AS available
FROM table
WHERE lid=1
Weird application of CTE's:
WITH lid AS (
SELECT DISTINCT lid FROM taken
)
, tak AS (
SELECT lid,taken , COUNT(*) AS cnt
FROM taken t0
GROUP BY lid,taken
)
SELECT l.lid
, COALESCE(a0.cnt, 0) AS available
, COALESCE(a1.cnt, 0) AS taken
FROM lid l
LEFT JOIN tak a0 ON a0.lid=l.lid AND a0.taken = 0
LEFT JOIN tak a1 ON a1.lid=l.lid AND a1.taken = 1
WHERE l.lid=1
;