passing a value in SQL - mysql

Question

I'm not sure I picked the correct title, but I did my best to explain what I am trying to do. I am just learning about joins and I have two tables that I am trying to combine in a certain way, but they both have WHERE clauses.
I started out by building both SELECT statements separately. Here is my first one from the table: "shipping_zones"
SELECT MIN(cal_zone) AS output_zone
FROM (
SELECT carrier, dest_zip, origin_zip, zone, MIN(zone) OVER(PARTITION BY carrier) as cal_zone
FROM shipping_zones z
WHERE (origin_zip = 402 OR origin_zip = 950) AND dest_zip = 015
) as t
WHERE zone=cal_zone;
This returns:
+-------------+
| output_zone |
+-------------+
| 5 |
+-------------+
My second table is: "shipping_prices" and my query is:
SELECT carrier, speed, zone, min_price
FROM (SELECT carrier, zone, speed, price, MIN(price) OVER(PARTITION BY speed) as min_price
FROM shipping_prices
WHERE total_wt = 66 and zone = 6
) t
WHERE price=min_price
ORDER BY speed DESC;
and the result is:
+---------+-------+------+-----------+
| carrier | speed | zone | min_price |
+---------+-------+------+-----------+
| fedex | slow | 6 | 45.66 |
| usps | med | 6 | 96.05 |
| usps | fast | 6 | 347.15 |
+---------+-------+------+-----------+
What I want to do is "pass" the value for output_zone from the first query as an "argument" into the 2nd query. I put argument word in quotes because I'm not sure that is the correct word.
I the best to accomplish this in SQL is to use a join correct? I understand the basic syntax of a join but am a bit lost because of clauses I'm using in both (WHERE, MIN, ORDER BY, etc.)
EDIT: This data is bring queried with Impala and was created in MySQL before being imported into HDFS with HIVE.
EDIT2: I should also mention that the "shipping_prices" table already has a field in it called "zone". So I guess I wouldn't be "passing" it so much as using its value from the output of the first query to find the appropriate tuples in the "shipping_prices" table.
Any help or tips would be appreciated.

Answer 1

Simply you can put your first query into one zone in (first_query) statement to replace zone=6.
The codes will be like below:
SELECT carrier, speed, zone, min_price
FROM (SELECT carrier, zone, speed, price, MIN(price) OVER(PARTITION BY speed) as min_price
FROM shipping_prices
WHERE total_wt = 66
and zone in (
SELECT MIN(cal_zone) AS output_zone
FROM (
SELECT carrier, dest_zip, origin_zip, zone, MIN(zone) OVER(PARTITION BY carrier) as cal_zone
FROM shipping_zones z
WHERE (origin_zip = 402 OR origin_zip = 950) AND dest_zip = 015
) as t
WHERE zone=cal_zone;
)
) t
WHERE price=min_price
ORDER BY speed DESC;
It seems you are using Mysql 8.0 (Development Release), The Mysql Engine will do reasonable query optimization which will most likely rewrite both IN and JOIN queries to the same plan. Check this URL for the details Convert IN to JOIN