数据库增量备份和还原（如何在Perl或Java中实现）

Question

I have several Sqlite databases, which will be updated daily. So I need to do daily backup, in case if any crash happens so I can restore. However, it is costly to backup the whole database everyday, so I'm thinking of doing incremental backup (only backup those information between two different dates).

Currently my database updating process is done in Perl, so I am wondering: does anyone know how can I perform incremental database backup/ recovery in Perl/ Matlab/ Java using script?

Thank you!

Yours Sincerely, Qiao.

Answer 1

1. Store the timestamp of when each row was changed in your tables (call it change_timestamp column).

2. Don't delete rows - instead, mark them with "D" deleted status. This way you don't have to break your head/back figuring out which rows were deleted since last backup.

3. Have a "backup times" table

4. When you run a backup:

   • Save current run time into "backup times" table

   • Retrieve the last 2 rows from "backup times" table (If <2 rows, do full backup)

   • Back up main table rows where change_timestamp is between the 2 last backup timestamps.

You can do #1/#2 with judicious use of audit tables but it's a bit harder.