Tim Uckun wrote:

Hi.

Sorry for being so dense but...

The document says

The transaction handle is freed. It and its cursors must not be used again after this call, except with mdb_cursor_renew().

I am still very confused about reusing transactions.

Keep reading.

If I commit or abort a read write transaction I can't reuse the transaction but I can re use the cursor? In the cursor documentation it says

Cursors that are only used in read-only transactions may be re-used, to avoid unnecessary malloc/free overhead.

So this indicates only read only cursors can be reused right?

Yes.

So can you confirm my understanding? This is what I get from reading the docs.

A transaction can either be read write or read only.

If a transaction is read only you can commit or abort the transaction and then re-open it again for further use.

No. Once a transaction is committed or aborted it is freed and cannot be reused. Period, end of story. Both the commit() and abort() docs are quite explicit about this.

If a transaction is read write then it can't be used again after you commit or abort the transaction.

On Tue, Nov 22, 2016 at 3:17 PM, Howard Chu <hyc@symas.com mailto:hyc@symas.com> wrote:

Tim Uckun wrote:



        No. You can perform multiple write operations in a single transaction.


    But once the commit has been called the next write operation has to be
    a newly
    opened transaction right?  The write transactions can't be re-opened.

http://lmdb.tech/doc/group__mdb.html#ga846fbd6f46105617ac9f4d76476f6597
<http://lmdb.tech/doc/group__mdb.html#ga846fbd6f46105617ac9f4d76476f6597>