如果您需要来自这两个表的结果，您可以使用join和groupconcat以及groupby

"SELECT t1.id, t1.ruta, t1.destino, group_concat(t2.ref)  as ref
FROM table1 t1
INNER JOIN table2 t2 on t1.ruta = t2.ruta and t1.destino = t2.destino 
GROUP BY t1.id, t1.ruta, t1.destino "

考虑以下几点：

<?php

/*

DROP TABLE IF EXISTS t1;

CREATE TABLE t1
( id SERIAL PRIMARY KEY
, ruta CHAR(3) NOT NULL
);

INSERT INTO t1 VALUES
(1,'M17'),
(2,'M11');

DROP TABLE IF EXISTS t2;

CREATE TABLE t2
(id SERIAL PRIMARY KEY
,ref CHAR(3) NOT NULL
,ruta CHAR(3) NOT NULL
);

INSERT INTO t2 VALUES
(1,'A01','M17'),
(2,'A08','M17'),
(3,'A09','M17'),
(4,'A11','M17'),
(5,'A41','M11'),
(6,'A15','M11');

 SELECT t1.*
      , t2.ref
   FROM t1
   JOIN t2
     ON t2.ruta = t1.ruta
  ORDER
     BY t1.id
      , t2.id;
+----+------+-----+
| id | ruta | ref |
+----+------+-----+
|  1 | M17  | A01 |
|  1 | M17  | A08 |
|  1 | M17  | A09 |
|  1 | M17  | A11 |
|  2 | M11  | A41 |
|  2 | M11  | A15 |
+----+------+-----+

* /

require('path/to/connection/stateme.nts');

$query = "
 SELECT t1.id
      , t1.ruta
      , t2.ref
   FROM t1
   JOIN t2
     ON t2.ruta = t1.ruta
  ORDER
     BY t1.id
      , t2.id;
";

$result = mysqli_query($conn,$query);

$array = array();

while($row = mysqli_fetch_assoc($result)){
$array[] = $row;
}

$new_array = array();

foreach($array as $row){

   $new_array[$row['id']]['id'] = $row['ruta'];
   $new_array[$row['id']]['ruta'][] = $row['ref'];

}

$json = json_encode($new_array);

echo($json);

/*

Outputs: {"1":{"id":"M17","ruta":["A01","A08","A09","A11"]},"2":{"id":"M11","ruta":["A41","A15"]}}

or something like that

* /

?>