MySQL show status - active or total connections?

Question

When I run show status like 'Con%' it shows the number of connections, which is 9972 and constantly growing. Is this an active number of connections or connections made in total?

Jacy

Answer 1

According to the docs, it means the total number throughout history:

Connections

The number of connection attempts (successful or not) to the MySQL server.

You can see the number of active connections either through the Threads_connected status variable:

Threads_connected

The number of currently open connections.

mysql> show status where `variable_name` = 'Threads_connected';
+-------------------+-------+
| Variable_name     | Value |
+-------------------+-------+
| Threads_connected | 4     |
+-------------------+-------+
1 row in set (0.00 sec)

... or through the show processlist command:

mysql> show processlist;
+----+------+-----------------+--------+---------+------+-------+------------------+
| Id | User | Host            | db     | Command | Time | State | Info             |
+----+------+-----------------+--------+---------+------+-------+------------------+
|  3 | root | localhost       | webapp | Query   |    0 | NULL  | show processlist | 
|  5 | root | localhost:61704 | webapp | Sleep   |  208 |       | NULL             | 
|  6 | root | localhost:61705 | webapp | Sleep   |  208 |       | NULL             | 
|  7 | root | localhost:61706 | webapp | Sleep   |  208 |       | NULL             | 
+----+------+-----------------+--------+---------+------+-------+------------------+
4 rows in set (0.00 sec)

Shattuck

Does a connection represent a user? So if there are 200 users on a page that makes database queries will be 200 connections? – Divert

Yes, can someone clarify it. I too have same question. Also, does these variables reset after every MySQL Services restart or after Server reboot ? – Plagal

@Diego Queiroz It's not that simple. If the developer both paid close attention and if there's only 1 database that needs to be connected to per user, then yes, each of these will be a user. But it's possible there are other utilities running or backup services that will also need to connect. – Voiceful

@Plagal Yes, after the server restarts, every connection needs to reconnect. Many programs/libraries will auto-connect so the # of connections might fill up quickly without explicitly doing anything. But MySQL won't keep any old connections after a restart. – Voiceful

mysql -e "SHOW STATUS WHERE variable_name = 'Threads_connected';" -bash: variable_name: command not found ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '= 'Threads_connected'' at line 1 – Chosen

Answer 2

SHOW STATUS WHERE `variable_name` = 'Threads_connected';

This will show you all the open connections.

Huckaback

mysql -e "SHOW STATUS WHERE variable_name = 'Threads_connected';" -bash: variable_name: command not found ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '= 'Threads_connected'' at line 1 – Chosen

Answer 3

You can also do

SHOW STATUS WHERE `variable_name` = 'Max_used_connections';

Cobaltous

max_used_connections is also useful – Bourbon

Shouldn't max_user_connections refer to the maximum number of user allowed to connect to the database at the same time? This reports the fixed variable of mysql, not an actual operative value. – Archangel

Answer 4

This is the total number of connections to the server till now. To find current conection status you can use

mysqladmin -u -p extended-status | grep -wi 'threads_connected\|threads_running' | awk '{ print $2,$4}'

This will show you:

Threads_connected 12

Threads_running 1  

Threads_connected: Number of connections

Threads_running: connections currently running some sql

Dissimilitude

Answer 5

To see a more complete list you can run:

show session status;

or

show global status;

See this link to better understand the usage.

If you want to know details about the database you can run:

status;

Deer

Answer 6

In order to check the maximum allowed connections, you can run the following query:

SHOW VARIABLES LIKE "max_connections";

To check the number of active connections, you can run the following query:

SHOW VARIABLES LIKE "max_used_connections";

Hope it helps.

Stink

SHOW VARIABLES LIKE "max_used_connections"; returned Empty set (0.00 sec) but SHOW STATUS WHERE variable_name = 'Max_used_connections'; with "`" around "variable_name" worked – Subconscious

SHOW STATUS WHERE variable_name = "max_used_connections"; – Tlemcen

max_used_connections shows the maximum number of connections used since the database started not the current active connections. Source: dev.mysql.com/doc/refman/8.0/en/… – Hypognathous

Answer 7

As per doc http://dev.mysql.com/doc/refman/5.0/en/server-status-variables.html#statvar_Connections

Connections

The number of connection attempts (successful or not) to the MySQL server.

Assuan

Answer 8

A GUI solutions of MySQL queries:

If someone wants to show all active connection without any MySQL code, then you can use Session Manager in dbForge Studio:

Simply, open Database > Session Manager in the upper menu, and you'll see all active connections:

It will do the same thing that is done by these MySQL commands:

show full processlist;
SELECT * FROM information_schema.PROCESSLIST p;
SELECT * FROM performance_schema.threads t;

Bayless

Answer 9

It should be the current number of active connections. Run the command processlist to make sure.

URL for reference: http://www.devdaily.com/blog/post/mysql/how-show-open-database-connections-mysql

EDIT: Number of DB connections opened Please take a look here, the actual number of threads (connections) are described here!

Dorelle

I've found the reference links useful. For example, show status like '%onn%'; is a very useful query. – Dyun

This answer is wrong and should be deleted. See the other answers. – Spectator

From dev.mysql.com/doc/refman/8.0/en/…: "The number of connection attempts (successful or not) to the MySQL server". It is NOT the number of active connections. – Firepower

All sorts of connect stats, Aborted_connects, Connections are cumulative. Max_used_connections is the high water mark, Threads_connected is current, but show processlist gives id values as well as what is going on. – Donohue