略微加速

PHP官方手册 - 互联网笔记

PHP - Manual: mysqli_result::fetch_all

2024-11-15

mysqli_result::fetch_all

mysqli_fetch_all

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

mysqli_result::fetch_all -- mysqli_fetch_allFetch all result rows as an associative array, a numeric array, or both

说明

面向对象风格

public mysqli_result::fetch_all(int $mode = MYSQLI_NUM): array

过程化风格

mysqli_fetch_all(mysqli_result $result, int $mode = MYSQLI_NUM): array

Returns a two-dimensional array of all result rows as an associative array, a numeric array, or both.

注意:

Prior to PHP 8.1.0, available only with mysqlnd.

参数

result

仅以过程化样式:由 mysqli_query()mysqli_store_result()mysqli_use_result()mysqli_stmt_get_result() 返回的 mysqli_result 对象。

mode

This optional parameter is a constant indicating what type of array should be produced from the current row data. The possible values for this parameter are the constants MYSQLI_ASSOC, MYSQLI_NUM, or MYSQLI_BOTH.

返回值

Returns an array of associative or numeric arrays holding result rows.

更新日志

版本 说明
8.1.0 Now also available when linking against libmysqlclient.

范例

示例 #1 mysqli_result::fetch_all() example

面向对象风格

<?php

mysqli_report
(MYSQLI_REPORT_ERROR MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost""my_user""my_password""world");

$result $mysqli->query("SELECT Name, CountryCode FROM City ORDER BY ID LIMIT 3");

$rows $result->fetch_all(MYSQLI_ASSOC);
foreach (
$rows as $row) {
    
printf("%s (%s)\n"$row["Name"], $row["CountryCode"]);
}

过程化风格

<?php

mysqli_report
(MYSQLI_REPORT_ERROR MYSQLI_REPORT_STRICT);
$mysqli mysqli_connect("localhost""my_user""my_password""world");

$result mysqli_query($mysqli"SELECT Name, CountryCode FROM City ORDER BY ID LIMIT 3");

$rows mysqli_fetch_all($resultMYSQLI_ASSOC);
foreach (
$rows as $row) {
    
printf("%s (%s)\n"$row["Name"], $row["CountryCode"]);
}

以上例程会输出:

Kabul (AFG)
Qandahar (AFG)
Herat (AFG)

参见

add a noteadd a note

User Contributed Notes 4 notes

up
85
jcastro at eftec dot cl
7 years ago
I tested using "fetch all" versus "while / fetch array" and :

fetch-all uses less memory (but not for so much).

In my case (test1 and test2): 147008,262848 bytes (fetch-all) versus 147112,262888 bytes (fetch-array & while.

So, about the memory, in both cases are the same.

However, about the performance
My test takes :350ms (worst case) using fetch-all, while it takes 464ms (worst case) using fetch-array, or about 35% worst using fetch array and a while cycle.

So, using fetch-all, for a normal code that returns a moderate amount of information is :
a) cleaner (a single line of code)
b) uses less memory (about 0.01% less)
c) faster.

php 5.6 32bits, windows 8.1 64bits
up
4
mail2magvay at rambler dot ru
3 years ago
By the way, this case pretty work's too:

$services = $mysqli->query("SELECT * FROM table1");

if($services && $services->num_rows>0){
    $services->fetch_all(MYSQLI_ASSOC);
}

foreach($services as $service){
    echo $service; //work properly, cause it implements Iterator 
}

That's mean in this case $services is a valid array (or empty array)
up
8
m dot amiot at otak-arts dot com
10 years ago
If you really need this function, you can just extend the mysqli_result class with a function like this one.

<?php
       
public function fetch_all($resulttype = MYSQLI_NUM)
        {
            if (
method_exists('mysqli_result', 'fetch_all')) # Compatibility layer with PHP < 5.3
               
$res = parent::fetch_all($resulttype);
            else
                for (
$res = array(); $tmp = $this->fetch_array($resulttype);) $res[] = $tmp;

            return
$res;
        }
?>
up
2
andrey at php dot net
11 years ago
Return value changed in 5.3.3 - between 5.3.0 and 5.3.2 (incl.) when the result set was empty NULL was returned. 5.3.3+ returns an empty array.
Also, mysqli_fetch_all works only for buffered result sets, which are the default for mysqli_query. MYSQLI_USE_RESULT will be supported in 5.3.4+
However, it makes little sense to use it this way, materialising unbuffered sets. In this case choose STORE_RESULT, and fetch_all won't copy the data, but reference it, as it is stored already in mysqlnd.

官方地址:https://www.php.net/manual/en/mysqli-result.fetch-all.php

北京半月雨文化科技有限公司.版权所有 京ICP备12026184号-3