MySQL Set query timeout method

First, in Libmysql, the Mysql_opt_read_timeout settings item is provided, and the Libmysql provides an API for setting related settings items.

The code is as follows

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Mysql_options: int stdcall Mysql_options (MYSQL *mysql,enum mysql_option option, const void *arg) { Dbug_enter ("Mysql_option"); Dbug_print ("Enter", ("option:%d", (int) option); Switch (option) { Case Mysql_opt_connect_timeout: mysql->options.connect_timeout= * (uint*) arg; Break /** Read Timeout time * * Case Mysql_opt_read_timeout: mysql->options.read_timeout= * (uint*) arg; Break Case Mysql_opt_write_timeout: mysql->options.write_timeout= * (uint*) arg; Break Case Mysql_opt_compress: Mysql->options.compress= 1;

/* the following omitted * * *

However, unfortunately, only the mysqli extension, the mysql_options completely exposed to PHP:

The code is as follows

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Php_function (mysqli_options) { /** have omitted * * Switch (Z_TYPE_PP (mysql_value)) { /** without any restrictions, direct transmission to mysql_options * * Case is_string: ret = Mysql_options (Mysql->mysql, Mysql_option, Z_strval_pp (Mysql_value)); Break Default CONVERT_TO_LONG_EX (Mysql_value); L_value = z_lval_pp (Mysql_value); ret = Mysql_options (Mysql->mysql, Mysql_option, (char *) &l_value); Break } Return_bool (!ret); }

But since mysqli does not export this constant, we need to look at the MySQL code, get the actual value of Mysql_opt_read_timeout, and then call Mysql_options directly:

The code is as follows

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Enum Mysql_option { Mysql_opt_connect_timeout, Mysql_opt_compress, Mysql_opt_named_pipe, Mysql_init_command, Mysql_read_default_file, Mysql_read_default_group, Mysql_set_charset_dir, Mysql_set_charset_name, Mysql_opt_local_infile, Mysql_opt_protocol, Mysql_shared_memory_base_name, Mysql_opt_read_timeout, Mysql_opt_write_timeout, Mysql_opt_use_result, Mysql_opt_use_remote_connection, Mysql_opt_use_embedded_connection, Mysql_opt_guess_connection, Mysql_set_client_ip, Mysql_secure_auth, Mysql_report_data_truncation, Mysql_opt_reconnect, Mysql_opt_ssl_verify_server_cert };

As you can see, the mysql_opt_read_timeout is 11.

Now, we can set the query timeout:

<?php

The code is as follows	Copy Code
$mysqli = Mysqli_init (); $mysqli->options (one/*mysql_opt_read_timeout*/, 1); $mysql->real_connect (* * *);

However, because there is a retry mechanism in the libmysql (try it once and try it twice), we eventually set the time-out threshold three times times the value we set.

In other words, if we set the Mysql_opt_read_timeout to 1, we end up with a timeout after 3s. In other words, the minimum timeout we can set today is 3 seconds ...

Although the big point, but always better than no, hehe