How do I join two columns in a table?

How do you join a table with two columns?

If you'd like to get data stored in tables joined by a compound key that's a primary key in one table and a foreign key in another table, simply use a join condition on multiple columns. In one joined table (in our example, enrollment ), we have a primary key built from two columns ( student_id and course_code ).

How do I merge two columns in a table in SQL?

Multiple tables can be merged by columns in SQL using joins. Joins merge two tables based on the specified columns (generally, the primary key of one table and a foreign key of the other).

How do I merge two columns in a single column in SQL?

To merge two columns value as one, we can concatenate it as one and use alias for that value. This is the simplest way to do it. Here the combination of FirstName and LastName is separated by a blank space and given as FullName.

How do I merge two rows in a table in SQL?

SQL JOIN. A JOIN clause is used to combine rows from two or more tables, based on a related column between them. Notice that the "CustomerID" column in the "Orders" table refers to the "CustomerID" in the "Customers" table. The relationship between the two tables above is the "CustomerID" column.