Partition tables by week and setup maintenance code

[rorymckinley]

Partition the following tables by week:

• work_orders
• attempts
• runs
• log_lines

[jyeshe]

Hey @rorymckinley talked to @stuartc this morning and he accepted the approach we've talked about, to start with log_lines and measure the performance to decide about partitioning other tables.

[rorymckinley]

Hey @rorymckinley talked to @stuartc this morning and he accepted the approach we've talked about, to start with log_lines and measure the performance to decide about partitioning other tables.

@jyeshe Ok. I am going to look to preserve the work done on this so far, so it does not have to be repeated should we need to pick it up again (e.g. improved test coverage for the management of date-based partitions) and I will also restore the FKs removed by #1347.

[rorymckinley]

This is a 'mothballing' comment of the state of work on this issue:

#1392 is functional but needs to be tested against a DB. It contains code changes that will be useful if date-based partitioning is implemented on other tables.
#1453 requires code changes (see comments).
#1522 is WIP as it depends on #1453 being merged in (see the note about the shim migration). Tests are failing on this branch because I had to duplicate the Db changes of #1453 but I do not have the additional code form #1453. Once #1453 is merged in, the shim migration will be superfluous.

Once the above have been merged in, if the partitioning were to continue as originally envisaged, this is what remains:

• Setup partitions on attempts and runs
• Update the code that maintains the partitions so that any :all scopes also cover attempts and runs.