# Can db connections be shared **URL:** \ **Category:** Rails\ **Created:** [October 8, 2007, 3:47pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658 "2007-10-08T15:47:20Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 3:47pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/1 "2007-10-08T15:47:20Z")
If I have an application that makes numerous calls to a database for CRUD stuff over a period, does another user on a different PC when accessing the same database and same user make use of that existing connection. Or is another new connection opened, for the second user. When is the connection closed? When is it re-used? Is it any different if using multiple Mongrels and Proxy Load Balancer with Apache? Thanks Andrew ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 4:53pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/2 "2007-10-08T16:53:34Z")
No, none of them are shared. Each one is a separate connection. It would be the same with multiple instances of mongrel. -Bill Andrew C. wrote: > Andrew – Sincerely, William P. ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:19pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/3 "2007-10-08T17:19:59Z")
On 8 Oct 2007, at 14:47, Andrew C. wrote: > If I have an application that makes numerous calls to a database for > CRUD stuff over a period, does another user on a different PC when > accessing the same database and same user make use of that existing > connection. Or is another new connection opened, for the second user. > > When is the connection closed? When is it re-used? Is it any different > if using multiple Mongrels and Proxy Load Balancer with Apache? Unless you start establishing connections by hand, each instance of mongrel has one database connection, which it will reuse until it dies. If you only had one mongrel then there would only ever be 1 connection. Fred ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:36pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/4 "2007-10-08T17:36:23Z")
On 8 Oct 2007, at 16:30, William P. wrote: > You will get multiple connections regardless of whether you create > them by hand, even if it’s using a named pipe. I fired up 2 > connections by hand to illustrate the point: What do you mean by “fire up 2 connections”. I always see one connection per mongrel (+ instances of query browser etc… obviously) ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:31pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/5 "2007-10-08T17:31:42Z")
You will get multiple connections regardless of whether you create them by hand, even if it’s using a named pipe. I fired up 2 connections by hand to illustrate the point: netstat -an | grep mysql.sock unix 2 [ACC] STREAM LISTENING 7235 /var/lib/mysql/mysql.sock unix 3 [] STREAM CONNECTED 2373005 /var/lib/mysql/mysql.sock unix 3 [] STREAM CONNECTED 2372935 /var/lib/mysql/mysql.sock -Bill Frederick C. wrote: > > – Sincerely, William P. ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:38pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/6 "2007-10-08T17:38:09Z")
You said “by hand”, which I assumed to mean running mysql from the command line. How are you creating a connection by hand with Mongrel? Frederick C. wrote: > > Frederick C. wrote: > > > > > > – Sincerely, William P. ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:41pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/7 "2007-10-08T17:41:05Z")
I read your post again. I misinterpreted it to read that if you create connections by hand, those connections would be shared. Just a misinterpretation. -Bill William P. wrote: > /var/lib/mysql/mysql.sock > > > > connection. Or is another new connection opened, for the second user. > > > – Sincerely, William P. ---
**Author:** ![aginghipster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/e9c0ed/32.png) [@aginghipster](https://www.ruby-forum.com/u/aginghipster)\ **Post date:** [October 8, 2007, 5:41pm UTC](https://www.ruby-forum.com/t/can-db-connections-be-shared/116658/8 "2007-10-08T17:41:40Z")
On 8 Oct 2007, at 16:37, William P. wrote: > You said “by hand”, which I assumed to mean running mysql from the > command line. How are you creating a connection by hand with Mongrel? Well obviously that creates extra connections. By ‘by hand’ I mean calling ActiveRecord::Base.establish\_connection. My point was that unless you go out of your way, your rails app will use one connection per instance of mongrel. Fred