2つのテーブルからjson配列に行を選択

Question

私は初心者の開発者であり、それを理解することは非常に困難です。 私を助けてください。

catbook

+----+---------+------------+ 
| id | cat_num | count_book | 
+----+---------+------------+ 
| 1 | 55555 |   21 | 
| 2 | 77777 |   40 | 
+----+---------+------------+ 

userbook

+----+-----------+--------------+------------+ 
| id | user_name | cat_userbook | read_count | 
+----+-----------+--------------+------------+ 
| 1 | Andy  |  55555 |   3 | 
| 2 | Andy  |  77777 |   5 | 
| 3 | Tom  |  55555 |   4 | 
| 4 | Tom  |  77777 |   8 | 
+----+-----------+--------------+------------+ 

コード

<?php 
require_once("config.php"); 

$user_name = "Andy"; 

$sql ="SELECT cat_userbook, read_count, count_book FROM userbook, catbook WHERE user_name LIKE '" . $user_name . "'"; 
$result = mysqli_query($db_connect, $sql); 
$response = array(); 

while ($row = mysqli_fetch_assoc($result)) { 

    $response[] = $row; 
} 
echo json_encode($response); 
mysqli_close($db_connect); 

結果：

[ 
{"cat_userbook":"55555","read_count":"3","count_book":"21"}, 
{"cat_userbook":"55555","read_count":"3","count_book":"40"}, 
{"cat_userbook":"77777","read_count":"5","count_book":"21"}, 
{"cat_userbook":"77777","read_count":"5","count_book":"40"} 
] 

が、それはので、私のために必要であるとして、私はこの結果をしたい：

[ 
{"cat_userbook":"55555","read_count":"3","count_book":"21"}, 
{"cat_userbook":"77777","read_count":"5","count_book":"40"} 
] 

Answer 1

あなたはこのように参加している場合：userbookは、uはuserbook X catbook

取得 をcatbook

私はあなたが探していると思います：

SELECT cat_userbook, read_count, count_book FROM userbook LEFT JOIN catbook ON catbook.catNum = userbook.cat_userbook WHERE user_name LIKE '" . $user_name . "'";