using sql count in a case statement

Question

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

Answer 1

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

Answer 2

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;

Answer 3

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";

Answer 4

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.

Answer 5

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

Answer 6

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