I am trying to write a query that joins a table to itself via a date table. The date table is populated with a day per row with dates for over 200 years (don't ask I didn't design it). It has a column for the date and one for previous working date (i.e. if its a Monday the prev date will be the previous Friday).

The other table lets call it Prices has a date column and an id to determine the type of price that comes once each day. I need to join Prices against itself via the date table to have each day alongside the previous day using the type column to determine which ones belong with each other.

```
Todays Date | Todays Price | Previous Working Day Date | Previous Working Day Price | Price Type

```

Any Ideas?