如何使用psql數據庫中的數據創建分層json？

Question

我使用PHP連接到我的psql數據庫，並有一些初始代碼連接到數據庫，訪問表並設置列到數組等。但是，我一直在努力獲取我的數據到所需的格式我的代碼已經在運行。我的輸入是Json分層數據格式，如下所示。

function getData() { 
    return { 
"name": "data", 
"children": [ 
    { 
    "name": "America", 
    "children": [ 
    { 
    "name": "MA", 
    "children": [ 
     {"name": "Westborough", "order": 30}, 
     {"name": "Southborough", "order":20} 
    ] 
    }, 
    { 
    "name": "NH", 
    "children": [ 
     {"name": "Nashua", "order": 12} 
    ] 
    }, 
    { 
    "name": "CA", 
    "children": [ 
     {"name": "SanFransico", "order": 17} 
    ] 
    } 
    ] 
} 
] 
}; 

這是我當前使用的PHP代碼：

<?php 

    // attempt a connection 
$dbh = pg_connect("host=localhost dbname=sample user=postgres"); 
if (!$dbh) { 
    die("Error in connection: " . pg_last_error()); 
}  

// execute query 
$sql = "SELECT * FROM dataset"; 
$result = pg_query($dbh, $sql); 
if (!$result) { 
    die("Error in SQL query: " . pg_last_error()); 
}  

//Sets the column at 1 to an array 
$arr = pg_fetch_all_columns($result, 1); 


// free memory 
pg_free_result($result);  

// close connection 
pg_close($dbh); 

?> 

這是數據庫表

感謝提前:)

Answer 1

的格式我只是給你編碼一個圓頂，你需要檢查你的腰帶

$dbh = pg_connect("host=localhost dbname=sample user=postgres"); 

$ret = array(); 
$ret['name'] = 'data'; 
$ret['children'] = get_chilren($dbh,0); 

return json_encode($ret); 


while ($line = pg_fetch_array($result)) { 

} 


function get_chilren($dbh,$parentid){ 
    var $cret = array(); 
    $sql = "select * from database where parentid=".$parentid 
    $cresult = pg_query($dbh, $sql); 
    if (!$cresult) { 
    echo "An error occured.\n"; 
    exit; 
    } 
    while($chil = pg_fetch_array($cresult)){ // fetch each row 
    $cret['name'] = $chil['name']; 
    $cc = get_chilren($dbh,$chil['id']); 
    if(is_array($cc)) 
    {//when it hava a child 
     $cret['children'] = $cc; 
    }else{ //not hava 
     $cret['order'] = $chil['order']; 
    } 
    } 
    return $cret; 
}