Mysql - Copy column to table3

[danIT]

Basic reporting system:

 

Table1 contains a Unique ID and a Grade (Added from SIMS)

|

Table2 contains that same Unique ID and the Admission Number (Pupil Details)

|

Table3 contains an Admission Number and a Comment (Report Content)

 

Table1 - Col1 = UniqueID and Col2 = Grade

 

Table2 - Col1 = UniqueID and Col2 = Admission Number

 

Table3 - Col1 = AdmissionNumber Col2 = Comment Col3 = GradeCopy

 

I need to copy the 'Grade' from 'Table1' to 'Table3' but match that against the Unique ID and Admission number held in 'Table2'.

 

I need GradeCopy(Table3) to match Grade(Table1) but check that the correct grade is matched against the correct admission number after being check against the Unique ID.