Php MySQL无法保存结果集

这是一个生产PHP/MySQL系统，已经运行了几个月，基本上没有问题

我偶尔会在MySQL查询中看到“无法保存结果集”错误，比如每隔几周就出现一次

我知道这可能是由一个大的结果集引起的，但这里的情况并非如此。在最近的一个例子中，它发生在通常不超过10行的小桌子上（行表示活动的游戏，它们在游戏结束后被移除——翻倍很多，但总是很小）

查询非常简单：

SELECT player_1_id, player_2_id FROM minuetServer_games 
WHERE  ( player_1_id = '1513399' OR player_2_id = '1513399' )  
AND last_action_time < SUBTIME( CURRENT_TIMESTAMP, '0 0:01:22.000' ) 
FOR UPDATE;

以下是cm_connectToDatabase的代码：

function cm_connectToDatabase( $inTrackStats = true) {
    global $databaseServer,
           $databaseUsername, $databasePassword, $databaseName,
           $cm_mysqlLink;

    $cm_mysqlLink =
        mysql_connect( $databaseServer, 
                       $databaseUsername, $databasePassword );


    // bunch of error handling if $cm_mysqlLink is false
    // ....
    }

请注意，“无法保存结果集”是mysql\u查询引发的警告。此外，该查询每天运行数百次，没有问题。此警告最多每隔几周出现一次。以下是几天前的最新堆栈跟踪：

Warning:  mysql_query() [<a href='function.mysql-query'>function.mysql-query</a>]: Unable to save result set in /home/jcr14/public_html/gameServer/server.php on line 11248

#0  cm_noticeAndWarningHandler(2, mysql_query() [<a href='function.mysql-query'>function.mysql-query</a>]: Unable to save result set, /home/jcr14/public_html/gameServer/server.php, 11248, Array ([inQueryString] => SELECT player_1_id, player_2_id FROM minuetServer_games WHERE  ( player_1_id = '1513399' OR player_2_id = '1513399' )  AND last_action_time <      SUBTIME( CURRENT_TIMESTAMP, '0 0:01:22.000' ) FOR UPDATE;,[inDeadlockFatal] => 0,[cm_mysqlLink] => Resource id #4))

#1  mysql_query(SELECT player_1_id, player_2_id FROM minuetServer_games WHERE  ( player_1_id = '1513399' OR player_2_id = '1513399' )  AND last_action_time <      SUBTIME( CURRENT_TIMESTAMP, '0 0:01:22.000' ) FOR UPDATE;, Resource id #4) called at [/home/jcr14/public_html/gameServer/server.php:11248]

#2  cm_queryDatabase(SELECT player_1_id, player_2_id FROM minuetServer_games WHERE  ( player_1_id = '1513399' OR player_2_id = '1513399' )  AND last_action_time <      SUBTIME( CURRENT_TIMESTAMP, '0 0:01:22.000' ) FOR UPDATE;, 0) called at [/home/jcr14/public_html/gameServer/server.php:5979]

这也被称为一天100次，没有问题。这是一张只有一行的表

周围的代码：

function cm_getNewSquare() {

    global $tableNamePrefix;

    // have it wrap around at the 32-bit unsigned max
    // because getMagicSquare6 takes a 32-bit unsigned seed.
    // we store it as a BIGINT to keep it from getting stuck on the same
    // square after four billion games

    $query = "SELECT next_magic_square_seed % 4294967296 ".
        "FROM $tableNamePrefix".
        "server_globals FOR UPDATE;";

    $result = cm_queryDatabase( $query );

编辑4：

表格结构：

mysql> describe minuetServer_games;
+-----------------------+---------------------+------+-----+---------+----------------+
| Field                 | Type                | Null | Key | Default | Extra          |
+-----------------------+---------------------+------+-----+---------+----------------+
| game_id               | bigint(20) unsigned | NO   | PRI | NULL    | auto_increment |
| creation_time         | datetime            | NO   |     | NULL    |                |
| last_action_time      | datetime            | NO   |     | NULL    |                |
| player_1_id           | int(10) unsigned    | NO   | MUL | NULL    |                |
| player_2_id           | int(10) unsigned    | NO   | MUL | NULL    |                |
| dollar_amount         | decimal(11,2)       | NO   | MUL | NULL    |                |
| amulet_game           | tinyint(3) unsigned | NO   | MUL | NULL    |                |
| amulet_game_wait_time | datetime            | NO   | MUL | NULL    |                |
| started               | tinyint(3) unsigned | NO   |     | NULL    |                |
| round_number          | int(10) unsigned    | NO   |     | NULL    |                |
| game_square           | char(125)           | NO   |     | NULL    |                |
| player_1_got_start    | tinyint(4)          | NO   |     | NULL    |                |
| player_2_got_start    | tinyint(4)          | NO   |     | NULL    |                |
| player_1_moves        | char(13)            | NO   |     | NULL    |                |
| player_2_moves        | char(13)            | NO   |     | NULL    |                |
| player_1_bet_made     | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_bet_made     | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_1_ended_round  | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_ended_round  | tinyint(3) unsigned | NO   |     | NULL    |                |
| move_deadline         | datetime            | NO   |     | NULL    |                |
| player_1_coins        | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_coins        | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_1_pot_coins    | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_pot_coins    | tinyint(3) unsigned | NO   |     | NULL    |                |
| settled_pot_coins     | tinyint(3) unsigned | NO   |     | NULL    |                |
| semaphore_key         | int(10) unsigned    | NO   |     | NULL    |                |
+-----------------------+---------------------+------+-----+---------+----------------+
26 rows in set (0.00 sec)

CREATE语句：

 "CREATE TABLE $tableName(" .
"game_id BIGINT UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT," .
"creation_time DATETIME NOT NULL,".
"last_action_time DATETIME NOT NULL,".
"player_1_id INT UNSIGNED NOT NULL," .
"INDEX( player_1_id )," .
"player_2_id INT UNSIGNED NOT NULL," .
"INDEX( player_2_id )," .
"dollar_amount DECIMAL(11, 2) NOT NULL,".
"INDEX( dollar_amount )," .
"amulet_game TINYINT UNSIGNED NOT NULL,".
"INDEX( amulet_game ),".
// wait for a random amount of time before
// settling on an opponent for an amulet game
"amulet_game_wait_time DATETIME NOT NULL,".
"INDEX( amulet_game_wait_time ),".
"started TINYINT UNSIGNED NOT NULL,".
"round_number INT UNSIGNED NOT NULL," .
// 36-cell square, numbers from 1 to 36, separated by #
// character
"game_square CHAR(125) NOT NULL,".
// flag set when each player requests the very first game
// state. This indicates that both are aware that the game
// has started, so leave penalties can be assessed
"player_1_got_start TINYINT NOT NULL,".
"player_2_got_start TINYINT NOT NULL,".
"player_1_moves CHAR(13) NOT NULL,".
"player_2_moves CHAR(13) NOT NULL,".
"player_1_bet_made TINYINT UNSIGNED NOT NULL,".
"player_2_bet_made TINYINT UNSIGNED NOT NULL,".
"player_1_ended_round TINYINT UNSIGNED NOT NULL,".
"player_2_ended_round TINYINT UNSIGNED NOT NULL,".
"move_deadline DATETIME NOT NULL,".
"player_1_coins TINYINT UNSIGNED NOT NULL, ".
"player_2_coins TINYINT UNSIGNED NOT NULL, ".
"player_1_pot_coins TINYINT UNSIGNED NOT NULL, ".
"player_2_pot_coins TINYINT UNSIGNED NOT NULL, ".
// coins in both pots that are common knowledge to both players
// (coins that have been matched by opponent to move on
// to next turn)
"settled_pot_coins TINYINT UNSIGNED NOT NULL, ".
"semaphore_key INT UNSIGNED NOT NULL ) ENGINE = INNODB;"

偶然出现虚假的“无法保存结果集”警告的原因是什么

遗憾的是，PHP手册中没有很好地记录此错误。那么，让我们来看看RTFS

查看您的

ext/mysql

版本的源代码时，出现错误

“无法保存结果集”

：

if（使用存储==MYSQL\u使用结果）{
mysql\u result=mysql\u use\u result（mysql->conn）；
}否则{
mysql\u result=mysql\u store\u result（mysql->conn）；
}
如果（！mysql_result）{
如果（PHP\u MYSQL\u VALID\u RESULT（MYSQL->conn））{/*查询应该返回行*/
php_错误_docref（空TSRMLS_CC，E_警告，“无法保存结果集”）；

查看

PHP\u MYSQL\u VALID\u结果的

#定义PHP_MYSQL_有效_结果（MYSQL）\
（mysql_字段_计数（mysql）>0）

很明显，要出现此错误，
mysql\u store\u result（）
必须返回
NULL
但
mysql\u field\u count（）
必须返回正数。后一个函数的mysql C API声明：

此函数的正常使用是在返回
NULL
（因此您没有结果集指针）时。在这种情况下，您可以调用以确定是否应生成非空结果。这使客户端程序能够在不知道查询是否是（或类似）语句的情况下采取适当的操作

好吧，这似乎正好描述了您的案例中出现的情况。以下链接：

成功调用后，可以返回
NULL
。发生这种情况时，表示出现以下情况之一：


出现
malloc（）
故障（例如，如果结果集太大）

无法读取数据（连接上发生错误）

查询没有返回任何数据（例如，它是一个、或）


由于该情况是在执行
SELECT
查询时出现的，并且没有任何连接错误的迹象（我认为如果是这种情况，客户端会删除该错误），因此该错误的最可能原因似乎是
malloc（）
failure。对
malloc（）
可能失败的情况给出了很好的解释

有办法解决吗

当然有，是的！但这很可能涉及到详细分析MySQL在本例中分配内存失败的原因。我猜您的托管环境限制了MySQL可用的内存，并且已经达到了内存分配

也许简单地增加MySQL的可用内存会有所帮助？否则，您可能希望通读并开始调整一些服务器设置

有可靠的工作吗

如果出现这种情况，您可以简单地重新尝试查询

---

我通过在服务器达到100%使用率时释放服务器磁盘空间来解决这个问题

---

此问题已记录在/var/log/mysql/error.log中，因此我总是在做任何事情之前先检查错误日志。

这是一个PHP错误，而不是mysql错误。要确定问题，您需要提供有关执行此命令的PHP上下文的进一步信息。不，不是phpinfo-！生成和执行此命令的PHP代码使用更新。首先-停止使用

mysql

扩展，因为它已被弃用。尝试重写您的代码以使用

mysqli

或

pdo

。@PaulTomkiel:对于一个显然是一个大型的现有代码库的现有项目，这现在可能不是一个非常有用的建议…@FélixGagnon Grenier:MySQL文档清楚地说明了可能发生此故障的情况，这不是由于锁冲突造成的（这通常只会导致一个查询排队，直到这些锁被释放，可能会超时，除非出现死锁，在这种情况下会引发错误）.Op在内存限制为96M的最大10行表上进行了测试。阅读ops文章第3段时，RTFS lulz。不管eggyal如何，都有很多好信息。@Brian：仅仅因为所讨论的查询很小并不意味着MySQL没有耗尽内存。例如，如果MySQL已经消耗了除1KB以外的所有内存分配，那么查询仍可能导致

malloc（）

失败。不确定你的第二句话是什么意思？奇怪的是，错误和警告是通过我的自定义日志机制记录的，它实际上从同一个线程和连接将日志条目插入到同一个数据库中。再加上每天有20K个查询正常运行

function cm_getNewSquare() {

    global $tableNamePrefix;

    // have it wrap around at the 32-bit unsigned max
    // because getMagicSquare6 takes a 32-bit unsigned seed.
    // we store it as a BIGINT to keep it from getting stuck on the same
    // square after four billion games

    $query = "SELECT next_magic_square_seed % 4294967296 ".
        "FROM $tableNamePrefix".
        "server_globals FOR UPDATE;";

    $result = cm_queryDatabase( $query );

mysql> describe minuetServer_games;
+-----------------------+---------------------+------+-----+---------+----------------+
| Field                 | Type                | Null | Key | Default | Extra          |
+-----------------------+---------------------+------+-----+---------+----------------+
| game_id               | bigint(20) unsigned | NO   | PRI | NULL    | auto_increment |
| creation_time         | datetime            | NO   |     | NULL    |                |
| last_action_time      | datetime            | NO   |     | NULL    |                |
| player_1_id           | int(10) unsigned    | NO   | MUL | NULL    |                |
| player_2_id           | int(10) unsigned    | NO   | MUL | NULL    |                |
| dollar_amount         | decimal(11,2)       | NO   | MUL | NULL    |                |
| amulet_game           | tinyint(3) unsigned | NO   | MUL | NULL    |                |
| amulet_game_wait_time | datetime            | NO   | MUL | NULL    |                |
| started               | tinyint(3) unsigned | NO   |     | NULL    |                |
| round_number          | int(10) unsigned    | NO   |     | NULL    |                |
| game_square           | char(125)           | NO   |     | NULL    |                |
| player_1_got_start    | tinyint(4)          | NO   |     | NULL    |                |
| player_2_got_start    | tinyint(4)          | NO   |     | NULL    |                |
| player_1_moves        | char(13)            | NO   |     | NULL    |                |
| player_2_moves        | char(13)            | NO   |     | NULL    |                |
| player_1_bet_made     | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_bet_made     | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_1_ended_round  | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_ended_round  | tinyint(3) unsigned | NO   |     | NULL    |                |
| move_deadline         | datetime            | NO   |     | NULL    |                |
| player_1_coins        | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_coins        | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_1_pot_coins    | tinyint(3) unsigned | NO   |     | NULL    |                |
| player_2_pot_coins    | tinyint(3) unsigned | NO   |     | NULL    |                |
| settled_pot_coins     | tinyint(3) unsigned | NO   |     | NULL    |                |
| semaphore_key         | int(10) unsigned    | NO   |     | NULL    |                |
+-----------------------+---------------------+------+-----+---------+----------------+
26 rows in set (0.00 sec)

 "CREATE TABLE $tableName(" .
"game_id BIGINT UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT," .
"creation_time DATETIME NOT NULL,".
"last_action_time DATETIME NOT NULL,".
"player_1_id INT UNSIGNED NOT NULL," .
"INDEX( player_1_id )," .
"player_2_id INT UNSIGNED NOT NULL," .
"INDEX( player_2_id )," .
"dollar_amount DECIMAL(11, 2) NOT NULL,".
"INDEX( dollar_amount )," .
"amulet_game TINYINT UNSIGNED NOT NULL,".
"INDEX( amulet_game ),".
// wait for a random amount of time before
// settling on an opponent for an amulet game
"amulet_game_wait_time DATETIME NOT NULL,".
"INDEX( amulet_game_wait_time ),".
"started TINYINT UNSIGNED NOT NULL,".
"round_number INT UNSIGNED NOT NULL," .
// 36-cell square, numbers from 1 to 36, separated by #
// character
"game_square CHAR(125) NOT NULL,".
// flag set when each player requests the very first game
// state. This indicates that both are aware that the game
// has started, so leave penalties can be assessed
"player_1_got_start TINYINT NOT NULL,".
"player_2_got_start TINYINT NOT NULL,".
"player_1_moves CHAR(13) NOT NULL,".
"player_2_moves CHAR(13) NOT NULL,".
"player_1_bet_made TINYINT UNSIGNED NOT NULL,".
"player_2_bet_made TINYINT UNSIGNED NOT NULL,".
"player_1_ended_round TINYINT UNSIGNED NOT NULL,".
"player_2_ended_round TINYINT UNSIGNED NOT NULL,".
"move_deadline DATETIME NOT NULL,".
"player_1_coins TINYINT UNSIGNED NOT NULL, ".
"player_2_coins TINYINT UNSIGNED NOT NULL, ".
"player_1_pot_coins TINYINT UNSIGNED NOT NULL, ".
"player_2_pot_coins TINYINT UNSIGNED NOT NULL, ".
// coins in both pots that are common knowledge to both players
// (coins that have been matched by opponent to move on
// to next turn)
"settled_pot_coins TINYINT UNSIGNED NOT NULL, ".
"semaphore_key INT UNSIGNED NOT NULL ) ENGINE = INNODB;"