Re: Regarding Transactions that span Multiple files

[Howard Chu <hyc@symas.com>]

Mohammed Muneer wrote:
> Create Env   - staff
> Create Env   - payroll
>
> Create Txn_staff
> Create Txn_payroll
>
> Begin write transaction for Txn_staff
>
> Insert staff data
>
>                  Set Txn_payroll parent to Txn_staff
>                  Begin write transaction for Txn_payroll
>
>                  Insert payroll data
>
>                  Commit Txn_payroll
>
> Commit Txn_staff
>
>
> ------------------------------------------------------------------
>
> Can the above Pseudocode work in lmdb ? Or in other words
> can a transactions span multiple env's?

No. But a single env can contain multiple DBs, and a txn can span multiple DBs 
within the same env:

Create Env
Create DB - staff
Create DB - payroll

mdb_txn_begin(env, NULL /*parent*/, &txn_staff) - 1st write txn
insert staff data
   mdb_txn_begin(env, txn_staff /*parent*/, &txn_payroll)
   insert payroll data
   mdb_txn_commit(txn_payroll)
mdb_txn_commit(txn_staff)

--
  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/