we want to do this check as fast as possible.
So Mir simply issues the INSERT. By this INSERT statement, a trigger gets,
-well, triggered that calculate a CRC-32 checksum of the comment and searches
-for rows with the same checksum. If it finds the checksum, the INSERT gets
-aborted. If the checksum isn't found, it is appended to the row and the
-INSERT is executed.
+well, triggered that calculates a CRC-32 checksum of the comment and
+searches for rows with the same checksum. If it finds the checksum, the
+INSERT gets aborted. If the checksum isn't found, it is appended to the row
+and the INSERT is executed.
The trigger works for INSERTs and UPDATEs.