mysql_unbuffered_query与mysql_query的区别
PHP mysql_data_seek() 函数 定义和用法 mysql_data_seek() 函数移动内部结果的指针。 语法 mysql_data_seek(data,row) 参数 描述 data 必需。返回类型为 resource 的结果集。该结果集从 mysql_query() 的调用中得到。 row 必需。想要设定的新的结果集指针的
PHP mysql_data_seek() 函数
定义和用法
mysql_data_seek() 函数移动内部结果的指针。
语法
mysql_data_seek(data,row)
参数
描述
data
必需。返回类型为 resource 的结果集。该结果集从 mysql_query() 的调用中得到。
row
必需。想要设定的新的结果集指针的行数。0 指示第一个记录。
说明
mysql_data_seek() 将 data 参数指定的 MySQL 结果内部的行指针移动到指定的行号。
接着调用 mysql_fetch_row() 将返回那一行。
row 从 0 开始。row 的取值范围应该从 0 到 mysql_num_rows – 1。
但是如果结果集为空(mysql_num_rows() == 0),要将指针移动到 0 会失败并发出 E_WARNING 级的错误,mysql_data_seek() 将返回 false。
返回值
如果成功则返回 true,失败则返回 false。
提示和注释
注释:mysql_data_seek() 只能和 mysql_query()一起使用,,而不能用于 mysql_unbuffered_query()。
例子
$conn = mysql_connect(‘localhost’,'root’,'root’);
mysql_query(‘set names gbk’);
mysql_select_db(‘pw8′,$conn);
$sql = "SELECT * FROM shop_district";
//$result = mysql_unbuffered_query($sql,$conn);
$result = mysql_query($sql,$conn);
while ($row = mysql_fetch_array($result, MYSQL_NUM)) {
printf ("ID: %s FID: %s Name: %s
", $row[0], $row[1], $row[2]);
}
mysql_data_seek($result,0);
while ($row = mysql_fetch_array($result, MYSQL_NUM)) {
printf ("ID: %s FID: %s Name: %s
", $row[0], $row[1], $row[2]);
}
mysql_free_result($result);

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