Re: Multiple threads and mdb_dbi_open

[Howard Chu <hyc@symas.com>]

Harry B wrote:
> Hello,
>
> As per the documentation here
> http://symas.com/mdb/doc/group__mdb.html#gac08cad5b096925642ca359a6d6f0562a
> I see the following,
>
> "This function must not be called from multiple concurrent transactions. A
> transaction that uses this function must finish (either commit or abort)
> before any other transaction may use this function."
>
> This seems to imply that after one txn has begun on an environment, I cannot
> create another txn or dbi until the first one has finished - that doesn't seem
> to be right.
>
> If I have multi-threaded app, what is the expected sequence for creation of
> Environment, Transaction, and DBI handles?

Before starting any other threads:
  Create the environment.
  Open a transaction.
  Open all DBI handles the app will need.
  Commit the transaction.

After that use the DBI handles freely among any transactions/threads.

> Any help is appreciated.
> --
> Harry


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