[sql] using sql count in a case statement

I have a table and i need to present the output in the following fashion.

tb_a:

col1  |  reg_id | rsp_ind 

Count of rows with rsp_ind = 0 as 'New' and 1 as 'Accepted'

The output should be

NEW | Accepted
9   | 10

I tried using the following query.

select 
  case when rsp_ind = 0 then count(reg_id)end as 'New',
  case when rsp_ind = 1 then count(reg_id)end as 'Accepted'
from tb_a

and i m getting output as

NEW | Accepted
NULL| 10
9   | NULL

Could someone help to me tweak the query to achieve the output. Note : I cannot add a sum surrounding this. Its part of a bigger program and so i cannot add a super-query to this.

This question is related to sql

The answer is


If you want to group the results based on a column and take the count based on the same, you can run the query as,

$sql = "SELECT COLUMNNAME,

COUNT(CASE WHEN COLUMNNAME IN ('YOURCONDITION') then 1 ELSE NULL END) as 'New',

COUNT(CASE WHEN COLUMNNAME IN ('YOURCONDITION') then 1 ELSE NULL END) as 'ACCPTED',

from TABLENAME

GROUP BY COLUMNANME";


The reason you're getting two rows instead of one is that you are grouping by rsp_ind in the outer query (which you did not, to my disappointment, share with us). There is nothing you can do to force one row instead of two without dealing with that GROUP BY item.


CREATE TABLE #CountMe (Col1 char(1));

INSERT INTO #CountMe VALUES ('A');
INSERT INTO #CountMe VALUES ('B');
INSERT INTO #CountMe VALUES ('A');
INSERT INTO #CountMe VALUES ('B');

SELECT
    COUNT(CASE WHEN Col1 = 'A' THEN 1 END) AS CountWithoutElse,
    COUNT(CASE WHEN Col1 = 'A' THEN 1 ELSE NULL END) AS CountWithElseNull,
    COUNT(CASE WHEN Col1 = 'A' THEN 1 ELSE 0 END) AS CountWithElseZero
FROM #CountMe;

ok. I solved it

SELECT `smart_projects`.project_id, `smart_projects`.business_id, `smart_projects`.title,
 `page_pages`.`funnel_id` as `funnel_id`, count(distinct(page_pages.page_id) )as page_count, count(distinct (CASE WHEN page_pages.funnel_id != 0 then  page_pages.funnel_id ELSE NULL END ) ) as funnel_count
FROM `smart_projects`
LEFT JOIN `page_pages` ON `smart_projects`.`project_id` = `page_pages`.`project_id`
WHERE  smart_projects.status !=  0 
AND `smart_projects`.`business_id` = 'cd9412774edb11e9'
GROUP BY `smart_projects`.`project_id`
ORDER BY `title` DESC

Depending on you flavor of SQL, you can also imply the else statement in your aggregate counts.

For example, here's a simple table Grades:

| Letters |
|---------|
| A       |
| A       |
| B       |
| C       |

We can test out each Aggregate counter syntax like this (Interactive Demo in SQL Fiddle):

SELECT
    COUNT(CASE WHEN Letter = 'A' THEN 1 END)           AS [Count - End],
    COUNT(CASE WHEN Letter = 'A' THEN 1 ELSE NULL END) AS [Count - Else Null],
    COUNT(CASE WHEN Letter = 'A' THEN 1 ELSE 0 END)    AS [Count - Else Zero],
    SUM(CASE WHEN Letter = 'A' THEN 1 END)             AS [Sum - End],
    SUM(CASE WHEN Letter = 'A' THEN 1 ELSE NULL END)   AS [Sum - Else Null],
    SUM(CASE WHEN Letter = 'A' THEN 1 ELSE 0 END)      AS [Sum - Else Zero]
FROM Grades

And here are the results (unpivoted for readability):

|    Description    | Counts |
|-------------------|--------|
| Count - End       |    2   |
| Count - Else Null |    2   |
| Count - Else Zero |    4   | *Note: Will include count of zero values
| Sum - End         |    2   |
| Sum - Else Null   |    2   |
| Sum - Else Zero   |    2   |

Which lines up with the docs for Aggregate Functions in SQL

Docs for COUNT:

COUNT(*) - returns the number of items in a group. This includes NULL values and duplicates.
COUNT(ALL expression) - evaluates expression for each row in a group, and returns the number of nonnull values.
COUNT(DISTINCT expression) - evaluates expression for each row in a group, and returns the number of unique, nonnull values.

Docs for SUM:

ALL - Applies the aggregate function to all values. ALL is the default.
DISTINCT - Specifies that SUM return the sum of unique values.


Close... try:

select 
   Sum(case when rsp_ind = 0 then 1 Else 0 End) as 'New',
   Sum(case when rsp_ind = 1 then 1 else 0 end) as 'Accepted'
from tb_a

select sum(rsp_ind = 0) as `New`,
       sum(rsp_ind = 1) as `Accepted` 
from tb_a