Basically, if your key column(s) in fact table don't have null values - it does not matter.
Try both and see if Number of Records changes. If it does - use LEFT join.
Using Inner Join We can display only matching records from fact and dimension table,but by using Left Join ,we can display
all records from fact table and matching records from dimension table.Based on Your Scenario you can select what type of
join you should have to use.
Sreenadha Reddy Palakolanu