mysql does not reconnect if connection was closed

[bgaifullin]

Issue description

if connection has been closed by idle timeout, further requests fails with error 'invalid connection'
seems like this behaviour was introduced by commit 26471af.

because the same code works on version 3955978

Configuration

Driver version (or git SHA):
7785c74

Go version: run go version in your console
go version go1.9 darwin/amd64

Server version: E.g. MySQL 5.6, MariaDB 10.0.20
Ver 5.7.16-10 for osx10.12 on x86_64 (Homebrew)

Server OS: E.g. Debian 8.1 (Jessie), Windows 10
OSX 10.12

[methane]

Duplicate of #657

[methane]

Summary: If your program start showing "invalid connection" after #302 (26471af),
your program might execute same query multiple times. If the query was not idempotent, you might broke your data.

You must not rely on old behavior. You must close connection from client side, before idle timeout.
Use DB.SetConnMaxLifetime(time.Second*10).

[bgaifullin]

I use "auto-commit" and there is only "read-only" queries :(

I think DB.SetConnMaxLifetime(%time less than mysql server idle timeout%), right ?

[methane]

But driver can't know your query is read only. You can retry by yourself, but I recommend short lifetime strongly. It saves you from many troubles.

On 2017年9月21日(木) 23:03 Bulat Gaifullin ***@***.***> wrote: I use "auto-commit" and there is only "read-only" queries :( I think DB.SetConnMaxLifetime(), right ? — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#670 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAMLqL8M0hG8pcw9nEV_ClF24k7LC0XHks5skmyagaJpZM4PfLDE> .

-- Inada Naoki <songofacandy@gmail.com>

[bgaifullin]

Ok.