![]() ![]() We can also use the left join with a WHERE condition. However, it fills the columns of the right table ( Sports_cars) with null as we can see the Row3, Row4, and Row5 in the output.Suppose, if the values are not similar, then the left join also generates a new row, which involves the columns from both tables and adds it to the outcome.If these records are similar, then the left join creates a new row, which is having the columns of both tables and adds the particular row to the result as we can see the Row1 and Row2 in the above output.In the above screenshot, the left join condition selects the records from the left table ( Luxury_cars), and it equates the values in the luxury_car_names column with the values in the sports_car_names column from the Sports_cars table.Once we implemented the above command, we will get the below result. SELECT L_ID, luxury_car_names, S_ID, sports_car_names In the below example, we will use the Create command to create a Luxury_cars table. Here, we will be creating and inserting the two different tables where we perform actions on several types of joins: Let us see some examples of different types of PostgreSQL joins: The below image displays most importantly used PostgreSQL joins, which we are going to explain in this section of the PostgreSQL tutorial. ![]() In PostgreSQL, we have various types of joins which are as follows: Usually, the standard columns of the first table are primary key columns and the second table columns are foreign key columns. It is used to merge columns from one or more tables according to the data of the standard columns between connected tables. Whenever we want to get records from two or more tables, we will execute the joins commands. And we can merge the Select and Joins statements together into a single command. PostgreSQL JOINS are used with SELECT command, which helps us to retrieve data from various tables. In this section, we are going to understand the working of several types of PostgreSQL joins, such as Inner join, Left join, Right join, and Full Outer join in brief. ![]()
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