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Need help optimizing your query

I have two tables - incoming tours(id,name)andincoming_tours_cities(id_parrent, id_city)

idin the first table is unique, and for each unique row from the first table there is a list id_city- s in the second table (i.e. id_parrentin the second table it is equal idfrom the first table)

for instance

incoming_tours

|--id--|------name-----|
|---1--|---first_tour--|
|---2--|--second_tour--|
|---3--|--thirth_tour--|
|---4--|--hourth_tour--|

incoming_tours_cities

|-id_parrent-|-id_city-|
|------1-----|---4-----|
|------1-----|---5-----|
|------1-----|---27----|
|------1-----|---74----|
|------2-----|---1-----|
|------2-----|---5-----|
........................

This means that it first_tourhas a list of cities -("4","5","27","74")

And second_tourthere is a list of cities -("1","5")

Suppose I have two values ​​- 4and 74:

Now I need to get all the rows from the first table, where the values ​​are both listed in the list of cities. that is, it should return only first_tour (because 4 and 74 are in this list of cities)

So I wrote the following query

SELECT t.name
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc0 ON tc0.id_parrent = t.id
AND tc0.id_city = '4'
JOIN `incoming_tours_cities` tc1 ON tc1.id_parrent = t.id
AND tc1.id_city = '74'

And it works great.

, ( 15), .

.

SELECT t.name
FROM `incoming_tours` t
JOIN `incoming_tours_cities` tc0 ON tc0.id_parrent = t.id
AND tc0.id_city = '4'
JOIN `incoming_tours_cities` tc1 ON tc1.id_parrent = t.id
AND tc1.id_city = '74'
.........................................................
JOIN `incoming_tours_cities` tc15 ON tc15.id_parrent = t.id
AND tc15.id_city = 'some_value'

45s ( , )

, ?

+5
6
SELECT t.name
FROM incoming_tours t INNER JOIN 
  ( SELECT id_parrent
    FROM incoming_tours_cities
    WHERE id IN (4, 74)
    GROUP BY id_parrent
    HAVING count(id_city) = 2) resultset 
  ON resultset.id_parrent = t.id

.

+6
SELECT name
FROM (
      SELECT DISTINCT(incoming_tours.name) AS name,
             COUNT(incoming_tours_cities.id_city) AS c
      FROM incoming_tours
           JOIN incoming_tours_cities
                ON incoming_tours.id=incoming_tours_cities.id_parrent
      WHERE incoming_tours_cities.id_city IN(4,74)
            HAVING c=2
      ) t1;

c=2 id_city, , , .

+2

, , , .

SELECT * FROM incoming_tours 
WHERE 
id IN (SELECT id_parrent FROM incoming_tours_cities WHERE id_city=4)
AND id IN (SELECT id_parrent FROM incoming_tours_cities WHERE id_city=74)
...
AND id IN (SELECT id_parrent FROM incoming_tours_cities WHERE id_city=some_value)
+1

. IN WHERE, , AND JOIN , .

0

,

SELECT t.name FROM `incoming_tours` as t WHERE t.id IN (SELECT id_parrent FROM `incoming_tours_cities` as tc WHERE tc.id_city IN ('4','74'));

, , ...

EDIT:

0

CTE . , . , ...

Declare @numCities int = 2

;with incoming_tours(id, name) AS
(
    select 1, 'first_tour' union all
    select 2, 'second_tour' union all
    select 3, 'third_tour' union all
    select 4, 'fourth_tour' 
)
, incoming_tours_cities(id_parent, id_city) AS
(
    select 1, 4 union all 
    select 1, 5 union all 
    select 1, 27 union all 
    select 1, 74 union all 
    select 2, 1 union all 
    select 2, 5
)
, cityIds(id_city) AS
( 
    select 4
    union all select 5
    /* Add all city ids you need to check in this table */
)
, common_cities(id_city, tour_id, tour_name) AS
(
    select c.id_city,  it.id, it.name
    from cityIds C, Incoming_tours_cities tc, incoming_tours it
    where C.id_city = tc.id_city
    and tc.id_parent = it.id
)
, tours_with_all_cities(id_city) As
(
    select tour_id from common_cities 
    group by tour_id 
    having COUNT(id_city) = @numCities
)
select it.name from incoming_tours it, tours_with_all_cities tic
where it.id = tic.id_city
0

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