sql code in Dax

TomMartens  thanks for this.

Now lets say I have a table with information regarding to the car park table A which gives the number of spaces in the car park area during a given timeframe.

Table B, is a calcuated table showing by date customers in the car park area, so for example on the 01/05/2019 1 customer was in car park zone A & left car park area, 3 customers were in car park zone B with 3 in left car park area.

I want to combine the two tables to say that when Date from table B is between 'from date' and 'to date' in table A and car park and car park area from B is equal to car park and car park area from table A then return the number of spaces in table B from table A. This should return table C 

And finally to create a measure which will return results in table d

Table A:

Table b:

Table c

then measures to show

01/05/2019 occupancy for carpark left zone b was (count(customerid)/30)= 3/30