I have the below table.

TableA

```
DaysInMonth    CalDate    CalendarMonth  MonthEndInd  CalDateMonth  WorkDay  HolidayInd
   31          3/26/2018     MAR 2018      N             3/31/2018     1         N
   31          3/25/2018     MAR 2018      N             3/31/2018     0         N

```

How can I calculate the number of WorkDays in a month?
I'm not sure where to start, so I don't have any work to show. 

Expected output 

```
DaysInMonth    CalDate    CalendarMonth  MonthEndInd  CalDateMonth  WorkDay  HolidayInd   WorkDaysInMonth
   31          3/26/2018     MAR 2018      N             3/31/2018     1         N
   31          3/25/2018     MAR 2018      N             3/31/2018     0         N

```

SQL I have the below but how can I add this to my query 

```
SELECT COUNT(*),C.CALENDAR_MONTH FROM HUM.CALENDAR C WHERE 1=1 AND C.WORKDAY = 1 GROUP BY C.CALENDAR_MONTH

```