![]() ![]() The following Venn diagram displays the PostgreSQL Right join where we can easily understand that the Right Join returns all the data from the Right table and only a similar data from the left table: PostgreSQL Right Join Syntax In PostgreSQL, the Right join is parallel to the Left Join condition, but it will give the opposite result of the join tables. Therefore, the Outer is the optional keyword, which is used in Right Join. The Right Join can also be called as the Right Outer Join clause. And if there are no corresponding records found from the Left table, it will return null values. The PostgreSQL Right JOIN or Right Outer Join is used to return all rows from the right table, and rows from the other table where the join condition is fulfilled defined in the ON condition. What is the PostgreSQL Right Outer Join or Right Join clause? We also learn how to use table-aliasing, WHERE clause, USING clause, and join multiple tables with the help of the PostgreSQL Right join clause. This article has explained how to use the INNER JOIN to combine three different tables in PostgreSQL.In this section, we are going to understand the working of PostgreSQL Right join, which is used to return data from the Right table. To avoid ambiguity, the tables’ columns must be specified with the table name. The “ON” clause is utilized with the INNER JOIN to define a joining condition. Postgres uses the INNER JOIN to get matching results from two or more tables based on the defined join conditions. The output demonstrates that the given three tables have been joined successfully. The second INNER JOIN is utilized to combine the emp_info table with the other two tables based on the “dpt_id” column: The first INNER JOIN is utilized to merge the “emp_bio” and “emp_details” tables based on the “e_id” column. The SELECT statement specifies the columns to be fetched from all three tables. Now use the INNER JOIN to combine the three given tables: SELECT emp_bio.e_name, emp_bio.emp_name, ![]() In the “emp_details” table, the “e_id” and “dpt_id” are foreign keys. The final table is “emp_details” which contains the following records: SELECT * FROM emp_details ![]() The “dpt_id” column is defined as a primary key in the “dpt_info” table. Now, run the “SELECT” command to fetch the results from the “dpt_info” table: SELECT * FROM dpt_info The “e_id” column is defined as a primary key in the “emp_bio” table. Let’s type the “SELECT *” command to fetch all the tables: SELECT * FROM emp_bio All three tables are connected via the foreign key constraint. Suppose we have already created three sample tables named “emp_bio”, “dpt_info”, and “emp_details''. The “ON” clause specifies the joining condition.Įxample: Joining Three Tables in Postgres The “INNER JOIN” joins the given tables on the basis of the defined JOIN condition. To avoid ambiguity, the tables’ columns must be specified with the table name, such as “tab_1.col_name”, “tab_2.col_name”, and tab_3.col_name. “tab_1”, “tab_2”, and “tab3” represents the tables to be joined. Use the below syntax to combine multiple tables using “INNER JOIN”: SELECT, , ![]() This post will explain how to use the Postgres INNER JOIN to merge three different tables. PostgreSQL supports various types of JOINS, such as “INNER JOIN”, “OUTER JOIN”, “NATURAL JOIN”, “SELF JOIN”, etc. To do that, the Joins can be used in databases. To get the related information from different tables, you might need to merge various tables. In relational databases, different tables are linked with each other using various constraints. PostgreSQL is a famous relational database that is freely available for all operating systems like Windows, Linux, and MacOS. ![]()
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