I have an application using SQLite with two tables a `master` table and a `scheduled` table.

I would like to update a value in the `master` table with the value in the scheduled table if I run a query some time after `due` has occurred. Once the `master` table is updated, I would like to delete those values from the `scheduled` table.

Imagine this is the starting state:

```
Table: master
   id    value 
   ---   -----
   1     "Buy"
   2     "Buy"

Table: scheduled
   key   id   value   due
   ----  ---  ------  -----
   1     1    "Sell"  2018-01-01 12:01:00
   2     2    "Sell"  2018-01-01 12:01:00
   3     1    "Buy"   2019-02-02 13:00:00

```

I'm trying to craft a query where if I run it after `2018-01-01 12:01:00`, I would like to see:

```
Table: master
   id    value 
   ---   -----
   1     "Sell"
   2     "Sell"

Table: scheduled
   key   id   value   due
   ----  ---  ------  -----
   3     1    "Buy"   2019-02-02 13:00:00

```

I'm new the SQLite, the closest I have gotten is the following:

```
UPDATE master
  SET
    value = (SELECT scheduled.value FROM scheduled WHERE scheduled.id = master.id)
  WHERE
    EXISTS (SELECT * FROM scheduled WHERE scheduled.due >= ?);

```

Unfortunately this doesn't seem to work, and I'm not even sure where to start on the `DELETE`.