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Consulta SQL em várias linhas


Outra abordagem seria -
SELECT housing_id
FROM mytable
WHERE facility_id IN (4,7)
GROUP BY housing_id
HAVING COUNT(DISTINCT facility_id) = 2

ATUALIZAÇÃO - inspirado pelo comentário de Josvic, decidi fazer mais alguns testes e pensei em incluir minhas descobertas.

Um dos benefícios de usar essa consulta é que é fácil modificar para incluir mais facilities_ids. Se você quiser encontrar todos os habitação_ids que tenham facilidade_ids 1, 3, 4 e 7, basta fazer -
SELECT housing_id
FROM mytable
WHERE facility_id IN (1,3,4,7)
GROUP BY housing_id
HAVING COUNT(DISTINCT facility_id) = 4

O desempenho de todas essas três consultas varia muito com base na estratégia de indexação empregada. Não consegui obter um desempenho razoável, no meu conjunto de dados de teste, da versão de subconsulta dependente, independentemente da indexação usada.

A solução de auto-junção fornecida por Tim funciona muito bem com índices separados de coluna única nas duas colunas, mas não funciona tão bem à medida que o número de critérios aumenta.

Aqui estão algumas estatísticas básicas na minha tabela de teste - 500k linhas - 147963 habitação_ids com valores potenciais para facilities_id entre 1 e 9.

Aqui estão os índices usados ​​para executar todos esses testes -
SHOW INDEXES FROM mytable;
+---------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+
| Table   | Non_unique | Key_name            | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type |
+---------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+
| mytable |          0 | UQ_housing_facility |            1 | housing_id  | A         |      500537 |     NULL | NULL   |      | BTREE      |
| mytable |          0 | UQ_housing_facility |            2 | facility_id | A         |      500537 |     NULL | NULL   |      | BTREE      |
| mytable |          0 | UQ_facility_housing |            1 | facility_id | A         |          12 |     NULL | NULL   |      | BTREE      |
| mytable |          0 | UQ_facility_housing |            2 | housing_id  | A         |      500537 |     NULL | NULL   |      | BTREE      |
| mytable |          1 | IX_housing          |            1 | housing_id  | A         |      500537 |     NULL | NULL   |      | BTREE      |
| mytable |          1 | IX_facility         |            1 | facility_id | A         |          12 |     NULL | NULL   |      | BTREE      |
+---------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+

A primeira consulta testada é a subconsulta dependente -
SELECT SQL_NO_CACHE DISTINCT housing_id
FROM mytable
WHERE housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=4)
AND housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=7);

17321 rows in set (9.15 sec)

+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+
| id | select_type        | table   | type            | possible_keys                                                  | key                 | key_len | ref        | rows   | Extra                                 |
+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+
|  1 | PRIMARY            | mytable | range           | NULL                                                           | IX_housing          | 4       | NULL       | 500538 | Using where; Using index for group-by |
|  3 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
|  2 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+

SELECT SQL_NO_CACHE DISTINCT housing_id
FROM mytable
WHERE housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=1)
AND housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=3)
AND housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=4)
AND housing_id IN (SELECT housing_id FROM mytable WHERE facility_id=7);

567 rows in set (9.30 sec)

+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+
| id | select_type        | table   | type            | possible_keys                                                  | key                 | key_len | ref        | rows   | Extra                                 |
+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+
|  1 | PRIMARY            | mytable | range           | NULL                                                           | IX_housing          | 4       | NULL       | 500538 | Using where; Using index for group-by |
|  5 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
|  4 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
|  3 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
|  2 | DEPENDENT SUBQUERY | mytable | unique_subquery | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | func,const |      1 | Using index; Using where              |
+----+--------------------+---------+-----------------+----------------------------------------------------------------+---------------------+---------+------------+--------+---------------------------------------+

Segue minha versão usando o GROUP BY ... HAVING COUNT ...
SELECT SQL_NO_CACHE housing_id
FROM mytable
WHERE facility_id IN (4,7)
GROUP BY housing_id
HAVING COUNT(DISTINCT facility_id) = 2;

17321 rows in set (0.79 sec)

+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+
| id | select_type | table   | type  | possible_keys                   | key         | key_len | ref  | rows   | Extra                                    |
+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+
|  1 | SIMPLE      | mytable | range | UQ_facility_housing,IX_facility | IX_facility | 4       | NULL | 198646 | Using where; Using index; Using filesort |
+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+

SELECT SQL_NO_CACHE housing_id
FROM mytable
WHERE facility_id IN (1,3,4,7)
GROUP BY housing_id
HAVING COUNT(DISTINCT facility_id) = 4;

567 rows in set (1.25 sec)

+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+
| id | select_type | table   | type  | possible_keys                   | key         | key_len | ref  | rows   | Extra                                    |
+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+
|  1 | SIMPLE      | mytable | range | UQ_facility_housing,IX_facility | IX_facility | 4       | NULL | 407160 | Using where; Using index; Using filesort |
+----+-------------+---------+-------+---------------------------------+-------------+---------+------+--------+------------------------------------------+

E por último, mas não menos importante, a auto-junção -
SELECT SQL_NO_CACHE a.housing_id
FROM mytable a
INNER JOIN mytable b
    ON a.housing_id = b.housing_id
WHERE a.facility_id = 4 AND b.facility_id = 7;

17321 rows in set (1.37 sec)

+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+-------------+
| id | select_type | table | type   | possible_keys                                                  | key                 | key_len | ref                     | rows  | Extra       |
+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+-------------+
|  1 | SIMPLE      | b     | ref    | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | IX_facility         | 4       | const                   | 94598 | Using index |
|  1 | SIMPLE      | a     | eq_ref | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | test.b.housing_id,const |     1 | Using index |
+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+-------------+

SELECT SQL_NO_CACHE a.housing_id
FROM mytable a
INNER JOIN mytable b
    ON a.housing_id = b.housing_id
INNER JOIN mytable c
    ON a.housing_id = c.housing_id
INNER JOIN mytable d
    ON a.housing_id = d.housing_id
WHERE a.facility_id = 1
AND b.facility_id = 3
AND c.facility_id = 4
AND d.facility_id = 7;

567 rows in set (1.64 sec)

+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+--------------------------+
| id | select_type | table | type   | possible_keys                                                  | key                 | key_len | ref                     | rows  | Extra                    |
+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+--------------------------+
|  1 | SIMPLE      | b     | ref    | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | IX_facility         | 4       | const                   | 93782 | Using index              |
|  1 | SIMPLE      | d     | eq_ref | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | test.b.housing_id,const |     1 | Using index              |
|  1 | SIMPLE      | c     | eq_ref | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | test.b.housing_id,const |     1 | Using index              |
|  1 | SIMPLE      | a     | eq_ref | UQ_housing_facility,UQ_facility_housing,IX_housing,IX_facility | UQ_housing_facility | 8       | test.d.housing_id,const |     1 | Using where; Using index |
+----+-------------+-------+--------+----------------------------------------------------------------+---------------------+---------+-------------------------+-------+--------------------------+