blocks|key|1487890|text|MySQL:错误1040:连接太多|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|1487891|这基本上告诉我们，MySQL同时处理最大数量的连接，默认情况下，它同时处理100连接。|1487892|以下原因会导致MySQL耗尽连接。|1487893|1487894|Slow+Queries|ordered-list-item|1487895|Data+Storage+Techniques|1487896|Bad+MySQL+Bad|1487897|1487898|通过执行以下操作，我能够克服这些问题。|1487899|打开MySQL+command+line+tool并键入，|CODE|1487900|show+variables+like+"max_connections";|code-block|syntax|javascript|1487901|这将返回类似于以下内容的内容。|1487902|%2B-----------------%2B-------%2B
%7C+Variable_name+++%7C+Value+%7C
%2B-----------------%2B-------%2B
%7C+max_connections+%7C+100+++%7C
%2B-----------------%2B-------%2B|1487903|您可以通过发出以下命令将设置更改为例如200，而不必重新启动MySQL服务器。|1487904|set+global+max_connections+=+200;|1487905|现在，当您下次重启MySQL时，它将使用此设置而不是默认设置。|1487906|请记住，增加连接数将增加运行MySQL所需的内存量。|1487907|entityMap^0|0|F|0|11|3|0|0|0|0|0|0|0|0|2|N|0|0|0|0|0|0|0|0|Q|0^^$0|@$1|2|3|4|5|6|7|1G|8|@$9|1H|A|1I|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1J|8|@$9|1K|A|1L|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|1M|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|1N|8|@]|D|@]|E|$]]|$1|K|3|L|5|M|7|1O|8|@]|D|@]|E|$]]|$1|N|3|O|5|M|7|1P|8|@]|D|@]|E|$]]|$1|P|3|Q|5|M|7|1Q|8|@]|D|@]|E|$]]|$1|R|3|-4|5|6|7|1R|8|@]|D|@]|E|$]]|$1|S|3|T|5|6|7|1S|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|1T|8|@$9|1U|A|1V|B|W]]|D|@]|E|$]]|$1|X|3|Y|5|Z|7|1W|8|@]|D|@]|E|$10|11]]|$1|12|3|13|5|6|7|1X|8|@]|D|@]|E|$]]|$1|14|3|15|5|Z|7|1Y|8|@]|D|@]|E|$10|11]]|$1|16|3|17|5|6|7|1Z|8|@]|D|@]|E|$]]|$1|18|3|19|5|Z|7|20|8|@]|D|@]|E|$10|11]]|$1|1A|3|1B|5|6|7|21|8|@]|D|@]|E|$]]|$1|1C|3|1D|5|6|7|22|8|@$9|23|A|24|B|C]]|D|@]|E|$]]|$1|1E|3|-4|5|6|7|25|8|@]|D|@]|E|$]]]|1F|$]]

MySQL: ERROR 1040: Too many connections

This basically tells that MySQL handles the maximum number of connections simultaneously and by default it handles 100 connections simultaneously. 

These following reasons cause MySQL to run out connections.

<ol>
<li>Slow Queries</li>
<li>Data Storage Techniques</li>
<li>Bad MySQL configuration</li>
</ol>

I was able to overcome this issues by doing the followings.

Open <code>MySQL command line tool</code> and type,

<pre><code>show variables like "max_connections";
</code></pre>

This will return you something like this.

<pre><code>+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 100 |
+-----------------+-------+
</code></pre>

You can change the setting to e.g. 200 by issuing the following command without having to restart the MySQL server.

<pre><code>set global max_connections = 200;
</code></pre>

Now when you restart MySQL the next time it will use this setting instead of the default.

Keep in mind that increase of the number of connections will increase the amount of RAM required for MySQL to run.

blocks|key|1483567|text|值得知道的是，如果服务器分区或驱动器上的可用磁盘空间耗尽，这也会导致MySQL返回此错误。如果您确定这不是实际的number+of+users+connected，那么下一步是检查您的MySQL服务器驱动器/分区上是否有可用的空间。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1483568|编辑2019年1月：|1483569|MySQL+5.7和5.8也是如此。我不知道这个版本以上的版本。|1483570|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/42196994/3536236^0|1K|P|0|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@$A|Q|B|R|1|S]]|C|$]]|$1|D|3|E|5|6|7|T|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|U|8|@]|9|@]|C|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|I|$J|$5|K|L|M|C|$N|O]]]]

It is worth knowing that if you run out of usable disc space on your server partition or drive, that this will also cause MySQL to return this error. If you're sure it's not the actual <a href="https://stackoverflow.com/a/42196994/3536236">number of users connected</a> then the next step is to check that you have free space on your MySQL server drive/partition.

Edit January 2019: 
This is true of MySQL 5.7 and 5.8 . I do not know for versions above this.

blocks|key|1730574|text|如果您像这样耗尽了连接，那么您很有可能没有关闭您已经打开的连接。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1730575|检查打开连接的代码，并确保尽快关闭连接。通常，您希望在实现IDisposable的任何对象(包括数据库连接)周围使用using关键字，以确保此类对象在离开需要它们的作用域时立即被释放。|1730576|您可以使用以下查询检查当前的活动连接数：|1730577|show+processlist|code-block|syntax|javascript|1730578|参考：MySQL+show+status+-+active+or+total+connections?|offset|length|1730579|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/q/7432241/141172^0|0|0|0|0|3|1C|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Y|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|Z|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|10|8|@]|9|@$M|11|N|12|1|13]]|A|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

If you are running out of connections like this, chances are excellent that you are not closing the connections that you have open.

Review code that opens connections and ensure the connections are closed as soon as practical. Typically you want to make use of the using keyword around anything that implements IDisposable (including database connections) to ensure that such objects are disposed as soon as they leave the scope where they are needed.

You can check the current number of active connections with this query:

<pre><code>show processlist
</code></pre>

Reference: <a href="https://stackoverflow.com/q/7432241/141172">MySQL show status - active or total connections?</a>

blocks|key|5257694|text|由于连接限制达到了在配置文件my.cnf中定义的最大限制，因此会发生此错误。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|5257695|为了修复这个错误，请以超级用户身份登录到MySQL+(注意:您可以以root用户身份登录，因为mysql会为root+user预先分配一个连接)，并使用以下命令增加max_connections变量：|BOLD|5257696|SET+GLOBAL+max_connections+=+500;|code-block|syntax|javascript|5257697|此更改将一直存在，直到下次服务器重新启动。为了使此更改永久生效，您必须在配置文件中进行修改。您可以通过以下方式完成此操作：|5257698|vi+/etc/my.cnf

[mysqld]
max_connections+=+500|5257699|This+article有详细的step+by+step+workaround+to+fix+this+error。看一看，希望能对你有所帮助。谢谢。|5257700|entityMap|0|LINK|mutability|MUTABLE|url|http://www.rathishkumar.com/2017/07/how-to-fix-mysql-too-many-connections.html|1^0|E|6|0|Y|4|1I|9|2A|F|0|0|0|0|0|C|0|T|S|1|0^^$0|@$1|2|3|4|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|15|8|@$9|16|A|17|B|C]|$9|18|A|19|B|C]|$9|1A|A|1B|B|H]]|D|@]|E|$]]|$1|I|3|J|5|K|7|1C|8|@]|D|@]|E|$L|M]]|$1|N|3|O|5|6|7|1D|8|@]|D|@]|E|$]]|$1|P|3|Q|5|K|7|1E|8|@]|D|@]|E|$L|M]]|$1|R|3|S|5|6|7|1F|8|@]|D|@$9|1G|A|1H|1|1I]|$9|1J|A|1K|1|1L]]|E|$]]|$1|T|3|-4|5|6|7|1M|8|@]|D|@]|E|$]]]|U|$V|$5|W|X|Y|E|$Z|10]]|11|$5|W|X|Y|E|$Z|10]]]]

This error occurs, due to connection limit reaches the maximum limit, defined in the configuration file <code>my.cnf</code>.
In order to fix this error, login to MySQL as <code>root</code> user (Note: you can login as root, since, mysql will pre-allocate additional one connection for <code>root user</code>) and increase the max_connections variable by using the following command:
<pre><code>SET GLOBAL max_connections = 500;
</code></pre>
This change will be there, until next server restart. In order to make this change permanent, you have to modify in your configuration file. You can do this by,
<pre><code>vi /etc/my.cnf

[mysqld]
max_connections = 500
</code></pre>
<a href="http://www.rathishkumar.com/2017/07/how-to-fix-mysql-too-many-connections.html" rel="nofollow noreferrer">This article</a> has detailed step by step <a href="http://www.rathishkumar.com/2017/07/how-to-fix-mysql-too-many-connections.html" rel="nofollow noreferrer">workaround to fix this error</a>. Have a look at it, I hope it may help you. Thanks.

blocks|key|3839951|text|您必须更改max_connections以增加允许的总连接数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3839952|并将max_user_connections重新设置为default+0+=>+no+limit，除非您需要限制此每用户连接。|BOLD|3839953|MySQL+Too+many+connections|3839954|entityMap|0|LINK|mutability|MUTABLE|url|https://dev.mysql.com/doc/refman/5.5/en/too-many-connections.html^0|5|F|0|2|K|14|8|0|0|Q|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@$9|W|A|X|B|C]|$9|Y|A|Z|B|H]]|D|@]|E|$]]|$1|I|3|J|5|6|7|10|8|@]|D|@$9|11|A|12|1|13]]|E|$]]|$1|K|3|-4|5|6|7|14|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

You have to change <code>max_connections</code> to increase total permitted connections.

And set <code>max_user_connections</code> back to default 0 => no limit unless you need to limit this per user connections.

<a href="https://dev.mysql.com/doc/refman/5.5/en/too-many-connections.html">MySQL Too many connections</a>

blocks|key|3840019|text|在您的程序中，您应该打开连接并保持打开状态，而不关闭它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3840020|我面临着同样的问题，并最终确定了。|3840021|我在try+catch之后添加了这段代码。|3840022|finally{
++++try+{
++++++++rs.close();
++++++++p.close();
++++++++conn.close();
++++}+catch+(SQLException+e)+{
++++++++//+TODO+Auto-generated+catch+block
++++++++e.printStackTrace();
++++}
}|code-block|syntax|javascript|3840023|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

In your program you would have opened the connections and left open without closing it.

I faced a same problem and finally identified.

I added this code, after try catch.

<pre><code>finally{
 try {
 rs.close();
 p.close();
 conn.close();
 } catch (SQLException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 }
}
</code></pre>

blocks|key|1483693|text|要查看为数据库配置了多少连接以供使用，请执行以下操作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1483694|select+@@max_connections;|code-block|syntax|javascript|1483695|要更改它，请执行以下操作：|1483696|set+global+max_connections+=+200;|1483697|要查看当前已连接的数量：|1483698|show+processlist;|1483699|我还编写了this+piece+of+software来帮助我随着时间的推移创建一个很好的事务电子表格，以便我可以跟踪哪些查询是问题所在：|offset|length|1483700|📷|atomic|1483701|​|1483702|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/CherryCircle/MySQLSlowLogAnalyzer|1|IMAGE|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/adfec656309e828c91b3a84dc474387c.png|imageAlt^0|0|0|0|0|0|0|5|M|0|0|0|1|1|0|0^^$0|@$1|2|3|4|5|6|7|1B|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|1C|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1D|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1E|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1F|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|1G|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1H|8|@]|9|@$Q|1I|R|1J|1|1K]]|A|$]]|$1|S|3|T|5|U|7|1L|8|@]|9|@$Q|1M|R|1N|1|1O]]|A|$]]|$1|V|3|W|5|6|7|1P|8|@]|9|@]|A|$]]|$1|X|3|-4|5|6|7|1Q|8|@]|9|@]|A|$]]]|Y|$Z|$5|10|11|12|A|$13|14]]|15|$5|16|11|17|A|$18|19|1A|-4]]]]

To see how many connections are configured for your DB to use:

<pre><code>select @@max_connections;
</code></pre>

To change it:

<pre><code>set global max_connections = 200;
</code></pre>

To see how many are connected at the current time:

<pre><code>show processlist;
</code></pre>

I also wrote <a href="https://github.com/CherryCircle/MySQLSlowLogAnalyzer" rel="nofollow noreferrer">this piece of software</a> to help me create a nice spreadsheet of transactions over time so I can track down which queries are the problem:
<a href="https://i.stack.imgur.com/Ojvh8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ojvh8.png" alt="enter image description here"></a>

blocks|key|1730640|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1730641|打开终端并键入以下命令：sudo+gedit+/etc/mysql/my.cnf|offset|length|style|CODE|1730642|将该行粘贴到my.cnf文件中：set-variable=max_connections=500|1730643|entityMap^0|0|C|S|0|G|W|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@$D|N|E|O|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|K|$]]

Try this : 

open the terminal and type this command : <code>sudo gedit /etc/mysql/my.cnf</code>

Paste the line in my.cnf file: <code>set-variable=max_connections=500</code>

blocks|key|1487924|text|检查您当前正在运行的应用程序是否仍在访问您的mysql，并且已经使用了所有的DB连接。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1487925|因此，如果你试图从工作台访问mysql，你会得到“连接太多”的错误。|1487926|停止您当前正在运行的web应用程序，它持有所有这些数据库连接，然后您的问题将得到解决。|1487927|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

Check if your current running application is still accessing your mysql and has consumed all the DB connections. 

So if you try to access mysql from workbench , you will get "too many connections" error.

stop your current running web application which is holding all those db connections and then your issue will be solved.

blocks|key|1730949|text|在https://dev.mysql.com/doc/refman/8.0/en/too-many-connections.html中清楚地指出了这个问题|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1730950|1730951|如果客户端在尝试连接到MySQL服务器时遇到太多连接错误，则其他客户端正在使用所有可用连接。|blockquote|1730952|1730953|1730954|我在几分钟后解决了这个问题，连接似乎被其他客户端释放了，我也尝试了同时重启vs和工作台。|1730955|entityMap|0|LINK|mutability|MUTABLE|url|https://dev.mysql.com/doc/refman/8.0/en/too-many-connections.html^0|1|1T|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@$A|U|B|V|1|W]]|C|$]]|$1|D|3|-4|5|6|7|X|8|@]|9|@]|C|$]]|$1|E|3|F|5|G|7|Y|8|@]|9|@]|C|$]]|$1|H|3|-4|5|6|7|Z|8|@]|9|@]|C|$]]|$1|I|3|-4|5|6|7|10|8|@]|9|@]|C|$]]|$1|J|3|K|5|6|7|11|8|@]|9|@]|C|$]]|$1|L|3|-4|5|6|7|12|8|@]|9|@]|C|$]]]|M|$N|$5|O|P|Q|C|$R|S]]]]

The issue noted clearly in <a href="https://dev.mysql.com/doc/refman/8.0/en/too-many-connections.html" rel="nofollow noreferrer">https://dev.mysql.com/doc/refman/8.0/en/too-many-connections.html</a>:

<blockquote>
 If clients encounter Too many connections errors when attempting to
 connect to the MySQL server, all available connections are in use by
 other clients.
</blockquote>

I got resolved the issue after a few minutes, it seems that connection was been released by other clients, also I tried with restarting vs and workbench at same time.

blocks|key|1730993|text|即使我将所有的连接都包装在使用语句中，我还是得到了这个错误。我忽略的一件事是这些连接保持开放的时间有多长。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1730994|我是这样做的：|1730995|using+(MySqlConnection+conn+=+new+MySqlConnection(ConnectionString))
{
++++conn.Open();
++++foreach(var+m+in+conn.Query<model>(sql))
++++{
++++++++//+do+something+that+takes+a+while,+accesses+disk+or+even+open+up+other+connections
++++}
}|code-block|syntax|javascript|1730996|记住，连接不会关闭，直到循环中的所有操作都完成，如果循环创建了更多的连接，它们就可以真正开始相加。|1730997|这样更好：|1730998|List<model>+models+=+null;
using+(MySqlConnection+conn+=+new+MySqlConnection(ConnectionString))
{
++++conn.Open();

++++models+=+conn.Query<model>(sql).ToList();+//+to+list+is+needed+here+since+once+the+connection+is+closed+you+can't+step+through+an+IEnumerable+++
}

foreach(var+m+in+models)
{
++++//+do+something+that+takes+a+while,+accesses+disk+or+even+open+up+other+connections
}|1730999|这样，您的连接就可以关闭，并在您执行其他操作之前释放回线程池|1731000|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|X|8|@]|9|@]|A|$G|H]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

I was getting this error even though I had all my Connections wrapped in using statements. The thing I was overlooking is how long those connections were staying open.

I was doing something like this:

<pre><code>using (MySqlConnection conn = new MySqlConnection(ConnectionString))
{
 conn.Open();
 foreach(var m in conn.Query&lt;model&gt;(sql))
 {
 // do something that takes a while, accesses disk or even open up other connections
 }
}
</code></pre>

Remember that connection will not close until everything in the loop is done and if the loop creates more connections, they can really start adding up.

This is better:

<pre><code>List&lt;model&gt; models = null;
using (MySqlConnection conn = new MySqlConnection(ConnectionString))
{
 conn.Open();

 models = conn.Query&lt;model&gt;(sql).ToList(); // to list is needed here since once the connection is closed you can't step through an IEnumerable 
}

foreach(var m in models)
{
 // do something that takes a while, accesses disk or even open up other connections
}
</code></pre>

That way your connection is allowed to close and is released back to the thread pool before you go to do other things

blocks|key|1731086|text|此问题主要发生在超过允许的到MySQL的最大并发连接数时。允许的最大连接数存储在全局变量max_connections中。您可以在MySQL中通过show+global+variables+like+max_connections;查看|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1731087|您可以通过以下步骤进行修复：|1731088|Step1:|BOLD|1731089|登录到MySQL并运行以下命令：SET+GLOBAL+max_connections+=+100;|1731090|现在登录到MySQL，连接太多的错误已修复。此方法不需要重新启动服务器。|1731091|Step2:|1731092|使用上面的step1可以解决这个问题，但是max_connections会在重启mysql时回滚到它的默认值。|1731093|为了使max_connection值永久存在，请更新my.cnf文件。|1731094|停止MySQL服务器：Service+mysql+stop|1731095|编辑配置文件my.cnf：vi+/etc/mysql/my.cnf|1731096|在mysqld部分下找到变量max_connections。|1731097|[mysql]|1731098|max_connections+=+300|1731099|设置为更高的值并保存文件。|1731100|启动服务器：Service+mysql+start|1731101|注意：在增加max_connections变量值之前，请确保服务器有足够的内存用于新请求和连接。|1731102|MySQL为每个连接预先分配内存，并仅在连接关闭时取消分配。当新的连接被查询时，系统需要有足够的内存、网络和计算能力来满足用户的请求。|1731103|此外，您还应该考虑增加MySQL服务器中的打开表数限制，以适应额外的请求。最后。关闭在服务器上完成事务的连接是非常重要的。|1731104|entityMap^0|21|17|0|0|0|6|0|G|X|0|0|0|6|0|0|0|B|I|0|D|K|0|0|0|7|0|0|L|0|0|6|J|0|0|3|0|0|0^^$0|@$1|2|3|4|5|6|7|1G|8|@$9|1H|A|1I|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1J|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|1K|8|@$9|1L|A|1M|B|J]]|D|@]|E|$]]|$1|K|3|L|5|6|7|1N|8|@$9|1O|A|1P|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|1Q|8|@]|D|@]|E|$]]|$1|O|3|P|5|6|7|1R|8|@$9|1S|A|1T|B|J]]|D|@]|E|$]]|$1|Q|3|R|5|6|7|1U|8|@]|D|@]|E|$]]|$1|S|3|T|5|6|7|1V|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|1W|8|@$9|1X|A|1Y|B|C]]|D|@]|E|$]]|$1|W|3|X|5|6|7|1Z|8|@$9|20|A|21|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|22|8|@]|D|@]|E|$]]|$1|10|3|11|5|6|7|23|8|@$9|24|A|25|B|C]]|D|@]|E|$]]|$1|12|3|13|5|6|7|26|8|@$9|27|A|28|B|C]]|D|@]|E|$]]|$1|14|3|15|5|6|7|29|8|@]|D|@]|E|$]]|$1|16|3|17|5|6|7|2A|8|@$9|2B|A|2C|B|C]]|D|@]|E|$]]|$1|18|3|19|5|6|7|2D|8|@$9|2E|A|2F|B|J]]|D|@]|E|$]]|$1|1A|3|1B|5|6|7|2G|8|@]|D|@]|E|$]]|$1|1C|3|1D|5|6|7|2H|8|@]|D|@]|E|$]]|$1|1E|3|-4|5|6|7|2I|8|@]|D|@]|E|$]]]|1F|$]]

This issue occurs mostly when the maximum allowed concurrent connections to MySQL has exceeded.
The max connections allowed is stored in the gloobal variable max_connections.
You can check it by <code>show global variables like max_connections;</code> in MySQL
You can fix it by the following steps:
Step1:
Login to MySQL and run this command: <code>SET GLOBAL max_connections = 100;</code>
Now login to MySQL, the too many connection error fixed. This method does not require server restart.
Step2:
Using the above step1 you can resolve ths issue but max_connections will roll back to its default value when mysql is restarted.
In order to make the max_connection value permanent, update the my.cnf file.
Stop the MySQL server: <code>Service mysql stop</code>
Edit the configuration file my.cnf: <code>vi /etc/mysql/my.cnf</code>
Find the variable max_connections under mysqld section.
<code>[mysql]</code>
<code>max_connections = 300</code>
Set into higher value and save the file.
Start the server: <code>Service mysql start</code>
Note:
Before increasing the max_connections variable value, make sure that, the server has adequate memory for new requests and connections.
MySQL pre-allocate memory for each connections and de-allocate only when the connection get closed. When new connections are querying, system should have enough resources such memory, network and computation power to satisfy the user requests.
Also, you should consider increasing the open tables limit in MySQL server to accommodate the additional request. And finally. it is very important to close the connections which are completed transaction on the server.

blocks|key|3840495|text|已通过重新启动数据库windows服务解决此问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3840496|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Problem resolved by restarting the database windows service

How to fix these, "SQL Error 1040: Too Many Connection"
even I try to put

<pre><code>max_user_connection=500
</code></pre>

still "Too many connection"

mySQL Error 1040: Too Many Connection

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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如何解决这些问题，"SQL Error 1040: Too Many“max_user_connection=500仍然“连接太多”

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