#TAble is ambiguous

Question

I am getting an error that states #Plans is ambiguous. This happens when I am joining a table to itself on a self join and am not sure why. Here is the code that leads to the error:

Alter Table #Plans
Add SecondPlanDate date

Update #Plans
Set 
    SecondPlanDate = Min (P2.PlanPurchaseDate) Over (Partition By P1.PatientID, P1.PlanPurchaseDate)
From
#Plans as P1
Inner Join
#Plans as P2
on
P1.PatientID = P2.PatientID
Where
P2.PlanPurchaseDate > P1.PlanPurchaseDate
;

Select
*
From
#Plans  

Any suggestions would be greatly appreciated.

Thanks,

Answer 1

I think you need to use the table alias:

UPDATE P1
SET P1.SecondPlanDate ...

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