I have a table with a field called type, where 3 various rows are possible: 1, 2 and 3.
Now, I don't care about 3 at all. I need to count how many rows there are with type = 1 and with type = 2. I am doing this with 2 queries, like this:
Query1: SELECT COUNT(id) as count FROM users WHERE type='1'
Query2: SELECT COUNT(id) as count FROM users WHERE type='2'
Can I do this with only 1 single query? If so, should I, or not? How would the query look?
SELECT type,
COUNT(id) AS count
FROM users
WHERE type IN ('1','2')
GROUP BY type
SELECT type, COUNT(id) AS count
FROM users
GROUP BY type
HAVING type < 3
SELECT sum(case when type = '1' then 1 else 0 end) as count_for_one,
sum(case when type = '2' then 1 else 0 end) as count_for_tow
FROM users
WHERE type IN ('1','2')
If you want separate numbers,
SELECT SUM(IF(type='1', 1, 0)), SUM(IF(type='2', 1, 0))
FROM users WHERE type IN ('1', '2')
Related
I have this table called tasks. I want to fetch count of the total task of each assign_date and on that date how many complete task by complete_date per user.
I want something like below
[{
user_id:1 ,
assign_date / compete_date : 2019-09-04,
assign_task : 2,
complete_task: 1
},
{
user_id:1 ,
assign_date / compete_date : 2019-09-19,
assign_task : 1,
complete_task: 2
}
]
Here's your query. using union all will get the count on both assigned and complete dates
select user_id
, complete_date as [assign_date / compete_date]
, sum(case when t1.s = 'assigned' then 1 else 0 end) as assign_task
, sum(case when t1.s = 'complete' then 1 else 0 end) as complete_task
from
(select user_Id, complete_date, 'complete' as s from task
union all
select user_Id, assign_date, 'assigned' as s from task) t1
group by t1.complete_date, t1.user_id
You can try below -
select user_id,date, count(assign_date) assign_task,count(compete_date) complete_task
from tablename
group by user_id,date
I have a table for exam result, how can I filter and count my "correct" values on my table and somehow group them by User Number and Module? for example, i only want to count my "correct" values:
SELECT
UserNo, ModuleNo, COUNT(QuestionResult) as correctanswers
FROM yourtablename
WHERE
QuestionResult='Correct'
GROUP BY
UserNo, ModuleNo
You have to group twice if you want it grouped by the user and the module.
First solution using SUM and CASE
SELECT `UserNo` ,
SUM(CASE WHEN `QuestionResult` = 'Correct' THEN 1 ELSE 0 END) AS QuestionResultCount ,
`Module`
FROM `TableName`
GROUP BY `UserNo` ,
`Module`
Second solution using COUNT and WHERE clause :
(Note: This could be better for large tables with proper indexes, since the DBE can use that index to filter the table while it can not be done with any CASE..WHEN based solutions.)
SELECT `UserNo` ,
COUNT(`QuestionResult`) AS QuestionResultCount ,
`Module`
FROM `TableName`
WHERE `QuestionResult` = 'Correct'
GROUP BY `UserNo` ,
`Module`
Third solution using COUNT and CASE :
SELECT `UserNo` ,
COUNT(CASE WHEN `QuestionResult` = 'Correct' THEN `QuestionResult` END) AS QuestionResultCount ,
`Module`
FROM `TableName`
GROUP BY `UserNo` ,
`Module`
SQLFiddle
Two alternatives:
Using CASE:
SELECT UserNo,
SUM(CASE WHEN QuestionResult = 'Correct' THEN 1 ELSE 0 END) as QuestionResult,
ModuleNo as Module
FROM TableName
GROUP BY `UserNo`,ModuleNo
ORDER BY ModuleNo,UserNo
Result:
USERNO QUESTIONRESULT MODULE
123456 3 1
987456 2 1
123456 4 2
987456 1 2
See result in SQL Fiddle.
Using WHERE caluse:
SELECT UserNo,
COUNT(QuestionResult) as QuestionResult,
ModuleNo as Module
FROM TableName
WHERE QuestionResult = 'Correct'
GROUP BY `UserNo`,ModuleNo
ORDER BY ModuleNo,UserNo
See result in SQL Fiddle.
Use COUNT
SELECT UserNo,
COUNT(QuestionResult)
FROM TABLE
WHERE QuestionResult = 'Correct'
GROUP BY ModuleNo, ModuleNo
The scenario is I have a column named "States" in a table, States can be 0,1,2,3 or 4. What I want to do is get a count of each state using WHERE State = in a single query.
The main purpose is I want to show the count of records (identified by their state). Like this, 20 records have State 0 etc.
Is this possible? If yes, then how can I achieve this?
Edit: I know about Count. Here's what I have tried:
SELECT State, Date_Created, (SELECT COUNT(Id) FROM [ECOS].[eco].[tb_projects_details] WHERE State=1) as State_One, (SELECT COUNT(Id) FROM [ECOS].[eco].[tb_projects_details] WHERE State=2) as State_Two, (SELECT COUNT(Id) FROM [ECOS].[eco].[tb_projects_details] WHERE State=0) as State_Zero, (SELECT COUNT(Id) FROM [ECOS].[eco].[tb_projects_details] WHERE State=4) as State_Four FROM [ECOS].[eco].[tb_projects_details] WHERE Date_Created < dateadd(week,-3,getdate());
If I understand it correctly, you want to group and count:
SELECT mt.States, COUNT(*) total
FROM my_table mt
GROUP BY mt.States
To generate a list of values and their counts you can do this:
SELECT State, COUNT(*) AS C
FROM mytable
GROUP BY State
To generate one row that contains value counts as columns you can do this:
SELECT
COUNT(CASE State WHEN 0 THEN 1 ELSE NULL END) AS State_0_Count,
COUNT(CASE State WHEN 1 THEN 1 ELSE NULL END) AS State_1_Count,
COUNT(CASE State WHEN 2 THEN 1 ELSE NULL END) AS State_2_Count,
COUNT(CASE State WHEN 3 THEN 1 ELSE NULL END) AS State_3_Count,
COUNT(CASE State WHEN 4 THEN 1 ELSE NULL END) AS State_4_Count
FROM [...]
WHERE [...]
It will be very easy if you use group by clause after where condition. Then you will get the number of each state very easily.
SELECT state, count(*)
FROM table_name
GROUP BY state
Next time read a sql for beginers book first.
Select state, count(*)
from table
group by state
I have two queries:
SELECT opr, COUNT(*) FROM table WHERE field = 'YES' GROUP BY opr
SELECT opr, MAX(category) FROM table WHERE field = 'NO' GROUP BY opr
So basically in the first query I am getting the number of transactions a user makes.
In the second query I am getting a category that all of those transactions fall under. I don't want to get all categories for each transaction they made, just the Max of the category field so that I have one entry per operator.
Until now, I have been catching both result sets in separate arrays and the looping through both arrays to get the complete opr->picks->category.
This doesn't always work it sometimes associates the wrong category to the wrong operator.
Is there a way to combine these two queries into one, so that I get the operator and picks, then the MAX(category)? The issue is that the conditions for each query are different on the field column.
SELECT opr,
COUNT(CASE WHEN field = 'YES' THEN 1 END) AS number_of_transactions,
MAX(CASE WHEN field = 'NO' THEN category END) AS category
FROM table
GROUP BY opr ;
The above logic can be attained in one query by using CASE
SELECT opr, COUNT(CASE WHEN `field` = 'YES' THEN opr END) as `count`,
MAX(CASE WHEN `field` = 'NO' THEN category END) as `max`
FROM table GROUP BY opr
Just add it in:
SELECT opr,count(*), MAX(category) FROM table WHERE field = 'YES' GROUP BY opr
You might also be able to drop it from 2 queries to 1 with this:
SELECT opr,count(*), MAX(category), field FROM table GROUP BY opr, field
even faster on the processor, use a sum bool:
select
opr,
sum(field='yes') as transactions,
max(if(field='no',category, null)) as category
from table
group by opr
I have a table with two columns:
column A column B
1 2
1 2
2 1
I want to return total of ones = 3 total of twos = 3
The best I can come up with is two queries like so:
SELECT sum(CASE WHEN columnA =1 THEN 1 ELSE 0 END )
+ sum(CASE WHEN columnB =1 THEN 1 ELSE 0 END )
SELECT sum(CASE WHEN columnA =2 THEN 1 ELSE 0 END )
+ sum(CASE WHEN columnB =2 THEN 1 ELSE 0 END )
Can this be done in one query?
Thanks
You didn't specify if you want to do this as 2 rows or as 2 values in a row.
Two rows are somewhat obvious (just union together all the values from each columns, and count(1) group by value against the result of the union; so I'll assume you want to do one row.
If you only have 1s or 2s, it's simple:
SELECT SUM(A+B-2) 'twos', SUM(4-A-B) 'ones' FROM myTable
SELECT SUM(IF(columnA=1, 1, 0) + IF(columnB=1, 1, 0)) as ones,
SUM(IF(columnA=2, 1, 0) + IF(columnB=2, 1, 0)) as twos
FROM myTable;
C.
To get everything in one query, I would try something like this.
SELECT Result.Val, COUNT(Result.Val) AS Count
FROM (
SELECT ColumnA AS Val
FROM TableName
UNION
SELECT ColumnB AS Val
FROM TableName
) AS Result
GROUP BY Result.Val
In general, you would count things like so:
SELECT columnA, COUNT(*) FROM myTable
GROUP BY columnA
to get the count of all different values in columnA.
SELECT COUNT(*) FROM table WHERE columnA=1 or columnB=1