Given the example SQL command below to do the following join: Select * from leftTable LEFT JOIN rightTable ON leftTable.column1 = rightTable.column1   What is one example thing you can create in your database to either avoid having to do the above join or reduce the cost of it?  Here are 3 example ideas to consider but if you choose one of these, describe exactly how it would avoid or reduce the cost of the above join:  creating an index on certain columns in the tables,  creating another table, or replacing the 2 tables used in the join with a different table

Given the example SQL command below to do the following join:

Select * from leftTable LEFT JOIN rightTable ON leftTable.column1 = rightTable.column1  

What is one example thing you can create in your database to either avoid having to do the above join or reduce the cost of it?  Here are 3 example ideas to consider but if you choose one of these, describe exactly how it would avoid or reduce the cost of the above join:  creating an index on certain columns in the tables,  creating another table, or replacing the 2 tables used in the join with a different table.