Multi-threaded processing: concurrent deleting the same row could throw the exception Row not found when trying to delete

MVStore transactions: a thread could see a change of a different thread within a different map. Pull request #153.

COLUMNS metatable

For compatibility with other databases, support for (double and float) -0.0 has been removed. 0.0 is used instead.

In version 1.4.186, order by was broken in some cases due to the change Make the planner use indexes for sorting when doing a GROUP BY. The change was reverted.

sequence on a column

instead of the old format (MM-dd HH:mm:ss). Patch by Richard Bull.