Basic Difference Between Join and Union
Joins are used to combine data into new columns. For example, if two tables are joined together, then the data from the first table is shown in one set of columns alongside the second table’s column in the same row.
Unions are used to combine data into new rows. For example, If two tables are “unioned” together, then the data from the first table is in one set of rows, and the data from the second table is in another set. The rows are in the same result.