Instruction For movies that are not in demand (rentals = 0 in May 2020), we want to remove them from our inventory. Write a query to return the number of unique inventory_id from those movies with 0 demand. Hint: a movie can have multiple inventory_id.

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Question 45

Movie inventory optimization

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***********

*** ****** **** *** *** ** ****** (******* = 0 ** *** 2020), ** **** ** ****** **** **** *** *********.
***** * ***** ** ****** *** ****** ** ****** *********_** **** ***** ****** **** 0 ******.
****: * ***** *** **** ******** *********_**.

Table 1: film

       ***_****       |  ***_****
----------------------+--------------------------
 ****_**              | *******
 *****                | ****
 ***********          | ****
 *******_****         | *******
 ********_**          | ********
 ********_********_** | ********
 ******_********      | ********
 ******_****          | *******
 ******               | ********
 ***********_****     | *******
 ******               | ****

Table 2: inventory

**** *** ** ******, ********_** ** *** ******* *** ** **** *****.

   ***_****   | ***_****
--------------+--------------------------
 *********_** | *******
 ****_**      | ********
 *****_**     | ********

Table 3: rental

   ***_****   | ***_****
--------------+--------------------------
 ******_**    | *******
 ******_**    | ********* **** **** ****
 *********_** | *******
 ********_**  | ********
 ******_**    | ********* **** **** ****
 *****_**     | ********

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