Sqlite – locked database

[David Harrison]

I have a bi-directional ordercomms interface and I

Topic

[David Barr]

You could probably use “catch”.

[James Cobane]

You can use ‘catch’ along with a ‘while’ loop to keep trying until the DB is available; i.e.

set retcd 1

while {$retcd} {

[David Harrison]

I’ve managed to find some information on the Sqlite website <a href="http://www.sqlite.org/tclsqlite.html#busy&#8221; class=”bbcode_url”>http://www.sqlite.org/tclsqlite.html#busy

It suggests setting a timeout to wait a while until the db is hopefully unlocked or using the ‘busy’ method but it doesn’t give any examples. Is this where the catch command comes in?

[Max Drown (Infor)]

Right. In James’ example above, the script will loop until the sql statement returns 1 (i.e., it ran successfully).

-- Max Drown (Infor)

[David Harrison]

I’ll run with that. Thanks

[Jim Kosloskey]

It might be prudent to put some limit so that you do not end up in that loop endlessly (that would not be good).

Of course then you need to determine what constitutes a prudent, useful limit.

email: jim.kosloskey@jim-kosloskey.com

[David Harrison]

That did occur to me so instead I’ve put in the line ‘db timeout 2000’ which, according to the documentation, should retry for 2 seconds during which time hopefully the database should no longer be locked. It seems the safer option as it’s a live ordercomms interface.

[Max Drown (Infor)]

David, how has this been working for you since you made your change?

-- Max Drown (Infor)

[David Harrison]

Max,

It’s worked ok as I haven’t had any ‘database locked’ errors with the code I’ve implemented it in. I have had the problem arise with other procs so you’ve prompted me to make the changes elsewhere.

Thanks,

Dave

[Author]

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