Inner Join of three tables with dirty data in MS SQL : I have three tables, T1, T2, T3

T1 has fields A, B, C
T2 has fields C, D, E
T3 has fields E, F, G

The idea is to inner join all of them to get table T

T must have fields A, B, C, D, E, F, G

I already now how to do the join of three tables, the problem is that the field E that is supposed to link T2 and T3 is very noisy, it supposed to be a numerical value, but it has all sort of values (text, punctuation, etc)

how would I use an if statement to do the inner join.

Thanks

Platform MS SQL

