Types Of Equi-Joins In SQL Explained
3 types of equi-joins: Foreign-key join (many-to-one), Homo-dimension join (one-to-one) & Primary-sub join (one-to-many). Each has unique characteristics & use cases, but most real-world scenarios fall into these 3 categories.
Let’s look at three types of equi-joins: Foreign-key join Two tables are associated by matching a certain field in table A with the primary key of table B (By field association, as we explained in the previous essay, it is the equivalence of corresponding values in fields specified by the joining condition). Table A is called the fact table, and table B the dimension table. The field in table A that will match table B’s primary key is table A’s foreign key that points to table B; table B is thus table A’s foreign key table. In this context, the primary key is a logical one, which is the fiel...