mysqli_stmt::send_long_data
mysqli_stmt_send_long_data
(PHP 5, PHP 7, PHP 8)
mysqli_stmt::send_long_data -- mysqli_stmt_send_long_data — Send data in blocks
说明
面向对象风格
过程化风格
Allows to send parameter data to the server in pieces (or chunks), e.g. if the
size of a blob exceeds the size of max_allowed_packet
.
This function can be called multiple times to send the parts of a character or
binary data value for a column, which must be one of the TEXT or BLOB datatypes.
参数
-
statement
仅以过程化样式:由 mysqli_stmt_init() 返回的 mysqli_stmt 对象。
param_num
-
Indicates which parameter to associate the data with. Parameters are numbered beginning with 0.
data
-
A string containing data to be sent.
示例
示例 #1 面向对象风格
<?php
$stmt = $mysqli->prepare("INSERT INTO messages (message) VALUES (?)");
$null = NULL;
$stmt->bind_param("b", $null);
$fp = fopen("messages.txt", "r");
while (!feof($fp)) {
$stmt->send_long_data(0, fread($fp, 8192));
}
fclose($fp);
$stmt->execute();
?>
参见
- mysqli_prepare() - 预处理执行 SQL
- mysqli_stmt_bind_param() - Binds variables to a prepared statement as parameters
+添加备注
用户贡献的备注 3 notes
ChrisH ¶
5 years ago
If you are trying to write a single field which is above max_allowed_packet then this function will not help you (contrary to what the documentation example seems to show above).
Parameters in MySQL are still restricted by max_allowed_packet on a per-field basis so you will get an error like:
“mysqli_sql_exception: Parameter of prepared statement which is set through mysql_send_long_data() is longer than 'max_long_data_size' bytes”
The only real use case for this function seems to be if you are writing multiple long fields which when combined would go over max_allowed_packet.
Gustavo Narea ¶
18 years ago
Just in case:
'max_allowed_packet' is a MySQL variable; it is not a PHP function/variable/constant.
Further info: http://dev.mysql.com/doc/refman/4.1/en/packet-too-large.html
HTH.
DimeCadmium ¶
4 years ago
To ChrisH's note, you must call this function multiple times with the same $param_nr, to send the first max_allowed_packet bytes, then the next, and so on. So you might need to do a for loop over changing substr() indexes, or etc.
备份地址:http://www.lvesu.com/blog/php/mysqli-stmt.send-long-data.php