SQLSTATE [HY000]：常规错误：2006 MySQL服务器已消失，无法创建临时表

Question

Everything I've seen is due to plugins or "weird" configurations or data sets.

I'm trying to do something very simple with PHP, MySQL, and PDO.

    $table_name = 'TEMP_' . time();
    $sql_commands = "CREATE TEMPORARY TABLE {$table_name} (X CHAR(1));";
    $conn = Database::factory();
    $stmt = $conn->prepare($sql_commands);
    $stmt->execute();

Database::factory() is essential returning a PDO object created from:

$opt = [
    PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
    PDO::MYSQL_ATTR_INIT_COMMAND => "SET time_zone = '" . TIME_ZONE . "';",
    PDO::MYSQL_ATTR_INIT_COMMAND => "SET SESSION group_concat_max_len = 10485760;",
];

$dsn = "mysql:dbname=$database;host=$hostname;port=$port;charset=utf8";

Every time I try to create temporary tables I get this error:

SQLSTATE[HY000]: General error: 2006 MySQL server has gone away

However the table does get created (At least, if I rerun too quick I get another error stating the table already exists.)

Contents of /etc/my.cnf

max_allowed_packet=128MB  # tried various values from 8MB up to 4GB
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
secure_file_priv=""
symbolic-links=0
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES 

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

For brevity of this post SHOW VARIABLES DUMP is pastebin'd.

Answer 1

Should your PREPARE and EXECUTE be followed by CLOSE to complete typical cycle?

max_allowed_packet=128MB should be max_allowed_packet=128M in your cnf

please post your error log into the question.