mysqli_result::$num_rows

mysqli_num_rows

(PHP 5, PHP 7, PHP 8)

mysqli_result::$num_rows -- mysqli_num_rows — Gets the number of rows in the result set

说明

面向对象风格

int|string $mysqli_result->num_rows;

过程化风格

mysqli_num_rows ( mysqli_result $result ) : int|string

Returns the number of rows in the result set.

The behaviour of mysqli_num_rows() depends on whether buffered or unbuffered result sets are being used. This function returns 0 for unbuffered result sets unless all rows have been fetched from the server.

参数

result: 仅以过程化样式：由 mysqli_query()、mysqli_store_result()、 mysqli_use_result()、mysqli_stmt_get_result() 返回的结果集标识。

返回值

An int representing the number of fetched rows. Returns 0 in unbuffered mode unless all rows have been fetched from the server.

Note:
If the number of rows is greater than PHP_INT_MAX, the number will be returned as a string.

范例

Example #1 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 Code, Name FROM Country ORDER BY Name");

/* Get the number of rows in the result set */
$row_cnt = $result->num_rows;

printf("Result set has %d rows.\n", $row_cnt);

Example #2 过程化风格


<?php

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

$result = mysqli_query($link, "SELECT Code, Name FROM Country ORDER BY Name");

/* Get the number of rows in the result set */
$row_cnt = mysqli_num_rows($result);

printf("Result set has %d rows.\n", $row_cnt);

以上例程会输出：

Result set has 239 rows.

参见

mysqli_affected_rows() - Gets the number of affected rows in a previous MySQL operation
mysqli_store_result() - 转移上一次查询返回的结果集
mysqli_use_result() - Initiate a result set retrieval
mysqli_query() - 对数据库执行一次查询
mysqli_stmt_num_rows() - Returns the number of rows fetched from the server

注释

Note:
In contrast to the mysqli_stmt_num_rows() function, this function doesn't have object-oriented method variant. In the object-oriented style, use the getter property.

User Contributed Notes

min0u 13-May-2017 02:56


This function doesn't work with LIMIT used jointly with SQL_CALC_FOUND_ROWS. If you want to obtain the total rows found you must do it manually, example:



<?php

public function errorList(int $limit=25,int $offset=0){

        $errorList = array();

        $result = $this->con->query("SELECT SQL_CALC_FOUND_ROWS id, erreur FROM Erreurs ORDER BY id DESC LIMIT $limit OFFSET $offset");

        while($row = $result->fetch_assoc()){

            $errorList[] = new Erreur($row);

        }

        $result->free();

        // $foundRows = $result->num_rows; // 25

        $foundRows = $this->con->query("SELECT FOUND_ROWS() as foundRows"); 

        $this->foundRows = $foundRows->fetch_assoc(); // 178

        return $errorList;

}

?>

justso at inbox dot ru 14-Nov-2015 09:36


in php 5.3.8 had unexpected troubles when checking for mysqli_result::$num_rows

If the result of the query is empty then var_dump of the result will be like this:

class mysqli_result#5 (5) {

  public $current_field => NULL

  public $field_count => NULL

  public $lengths => NULL

  public $num_rows => NULL

  public $type => NULL

}

but var_dump($result->num_rows) will give integer-typed zero instead of NULL:

int(0)

borisigna 07-Aug-2011 08:19


If you have problems making work this num_rows, you have to declare ->store_result() first.



<?php

$mysqli = new mysqli("localhost","root", "", "tables");



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

$query->execute();

$query->store_result();



$rows = $query->num_rows;



echo $rows;



// Return 4 for example

?>