Required help in a query

Question

I wanted to take count of records based on some condition.

Here's what the condition is.

data:

"col1"  "col2"  "col3
A   Y   Y
A   Y   Y
A   N   Y
A   N   Y
A   N   Y
A       Y
A       Y
A   N   Y
B   Y   N
B   Y   Y
B   N   Y
B   N   N
B   Y   Y
B   N   Y
C   Y   N
C   Y   Y
C   N   Y
C   Y   Y
C   N   Y
C   Y   Y

I need to take the count of Y from col3 excluding the N of col2 where the col1 value is A. My head is cracking when i think of doing it.

Note : N values of col2 must be excluded only where the col1 value is A. The null values also need to be included along with Y passing the criteria where the col3 value is Y.

Please help me.

I need to get the count as 11 if the query is correct.

Code i tried with.

Select
    'Yes' as "label",
    Count(*)    
FROM Table1
Where "date" between '2014-03-01' And '2014-03-05'
And
"col3" = 'Y' and ("col1"  'C' and "col2"  'N')

I have the idea to how to do it orally. By i couldn't figure out a way to do it in PostgreSQL.

Answer 1

Try with something like this:

Select
    'Yes' as "label",
    Count(*)    
FROM Table1
Where "date" between '2014-03-01' And '2014-03-05'
AND col3 = 'Y' AND NOT (col1='A' AND col2 IS NOT NULL AND col2='N')

Answer 2

You could consider the A and not A as two different cases try something like this:

Select 'Yes' as "label", Count(*)    
FROM Table1
Where "date" between '2014-03-01' And '2014-03-05'
and   "col3" = 'Y'
And   (("col1" = 'A' And "col2" <> 'N') Or ("col1" <> 'A'))

Answer 3

select
    count(col3 = 'Y' or null) - count(col2 = 'N' and col1 = 'A' or null) as "Yes"
from table1
where
    "date" between '2014-03-01' and '2014-03-05'