db_lmdb: do not error if dropping a non existent hard fork table

[moneromooo-monero]

No description provided.

[ghost]

Thanks for this. Was getting strange things in my log before crashing out.

2016-Sep-26 22:11:40.807598 Initializing cryptonote protocol...
2016-Sep-26 22:11:40.807651 Cryptonote protocol initialized OK
2016-Sep-26 22:11:40.808516 Initializing p2p server...
2016-Sep-26 22:11:41.111194 Set limit-up to 2048 kB/s
2016-Sep-26 22:11:41.111406 Set limit-down to 8192 kB/s
2016-Sep-26 22:11:41.111493 Set limit-up to 2048 kB/s
2016-Sep-26 22:11:41.111630 Set limit-down to 8192 kB/s
2016-Sep-26 22:11:41.118196 Binding on 192.168.0.21:18080
2016-Sep-26 22:11:41.118658 Net service bound to 192.168.0.21:18080
2016-Sep-26 22:11:41.118705 Attempting to add IGD port mapping.
2016-Sep-26 22:11:42.272478 Added IGD port mapping.
2016-Sep-26 22:11:42.272623 P2p server initialized OK
2016-Sep-26 22:11:42.272881 Initializing core rpc server...
2016-Sep-26 22:11:42.273044 Binding on 127.0.0.1:18081
2016-Sep-26 22:11:42.273437 Core rpc server initialized OK on port: 18081
2016-Sep-26 22:11:42.273492 Initializing core...
2016-Sep-26 22:11:42.274189 Loading blockchain from folder /home/XXXXX/.bitmonero/lmdb ...
2016-Sep-26 22:11:42.274278 option: fast
2016-Sep-26 22:11:42.274312 option: async
2016-Sep-26 22:11:42.274340 option: 1000
2016-Sep-26 22:11:42.275109 Failed to drop m_hf_starting_heights: MDB_NOTFOUND: No matching key/data pair found
2016-Sep-26 22:11:42.275553 Error opening database: Failed to drop m_hf_starting_heights: MDB_NOTFOUND: No matching key/data pair found
2016-Sep-26 22:11:42.275625 Deinitializing rpc server...
2016-Sep-26 22:11:42.275920 Deinitializing p2p...
2016-Sep-26 22:11:42.284355 Deinitializing core...
2016-Sep-26 22:11:42.285239 Closing IO Service.
2016-Sep-26 22:11:42.285444 Failed to deinitialize core...
2016-Sep-26 22:11:42.285554 Deinitializing cryptonote_protocol...

Note the duplicate entries at the top as well - quite strange.

2016-Sep-26 22:11:41.111194 Set limit-up to 2048 kB/s
2016-Sep-26 22:11:41.111406 Set limit-down to 8192 kB/s
2016-Sep-26 22:11:41.111493 Set limit-up to 2048 kB/s
2016-Sep-26 22:11:41.111630 Set limit-down to 8192 kB/s

[ghost]

Hmm...now getting this message instead:

2016-Sep-27 00:17:36.049535 Failed to query m_blocks: MDB_BAD_TXN: Transaction must abort, has a child, or is invalid
2016-Sep-27 00:17:36.051317 Error opening database: Failed to query m_blocks: MDB_BAD_TXN: Transaction must abort, has a child, or is invalid

My database was about at about 400k blocks before I pulled in the merges this evening which gave me the original errors above. So I've deleted my database and am starting to sync again from scratch.

[fluffypony]

Reviewed