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Move the pointer to the initial position of the data set in PHP_PHP tutorial

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WBOYOriginal
2016-07-13 10:44:29914browse

In php, we need to return the initial position of the data set through the mysql_data_seek function. See the code below

The code is as follows
 代码如下 复制代码

// Start snipit 1

$sql = "SELECT * from

";
$result = mysql_query($sql);

while ($row = mysql_fetch_assoc($result)) {
         // do stuff with $row
}

mysql_data_seek($result, 0); //关键是这儿

while ($row = mysql_fetch_assoc($result)) {
         // do other stuff with $row
}
?>

Copy code



// Start snippet 1

$sql = "SELECT * from "; $result = mysql_query($sql);


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

                // do stuff with $row

}

mysql_data_seek($result, 0); //The key is here

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

                // do other stuff with $row

}
?>

Definition and usage

The mysql_data_seek() function moves the internal result pointer.

mysql_data_seek(data,row) parameter description data required. Returns a result set of type resource. This result set is obtained from a call to mysql_query(). row required. The number of rows in the new result set pointer you want to set. 0 indicates the first record. Description mysql_data_seek() moves the row pointer within the MySQL result specified by the data parameter to the specified row number. Then calling mysql_fetch_row() will return that row. row starts from 0. The value range of row should be from 0 to mysql_num_rows - 1.
But if the result set is empty (mysql_num_rows() == 0), moving the pointer to 0 will fail with an E_WARNING level error and mysql_data_seek() will return false. Return value
Returns true if successful, false if failed.
http://www.bkjia.com/PHPjc/633101.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/633101.htmlTechArticleIn php, we need to return the initial position of the data set, which can be achieved by the mysql_data_seek function. See the code below. Copy the code as follows? // Start snipit 1 $sql = SELECT * from table; $result =...
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