![]() ![]() WHERE suppliers.supplier_id = orders.supplier_id Īnother type of join is called a PostgreSQL LEFT OUTER JOIN. Old SyntaxĪs a final note, it is worth mentioning that the PostgreSQL INNER JOIN example above could be rewritten using the older implicit syntax as follows (but we still recommend using the INNER JOIN keyword syntax): SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date The row for 500127 (order_id) from the orders table would be omitted, since the supplier_id 10004 does not exist in the suppliers table. ![]() The rows for Microsoft and NVIDIA from the supplier table would be omitted, since the supplier_id's 1003 do not exist in both tables. Our result set would look like this: supplier_id If we run the PostgreSQL SELECT statement (that contains an INNER JOIN) below: SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date We have another table called orders with three fields (order_id, supplier_id, and order_date). ![]() It contains the following data: supplier_id We have a table called suppliers with two fields (supplier_id and supplier_name). Let's look at some data to explain how the INNER JOINS work: This PostgreSQL INNER JOIN example would return all rows from the suppliers and orders tables where there is a matching supplier_id value in both the suppliers and orders tables. ON suppliers.supplier_id = orders.supplier_id Here is an example of a PostgreSQL INNER JOIN: SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date The PostgreSQL INNER JOIN would return the records where table1 and table2 intersect. In this visual diagram, the PostgreSQL INNER JOIN returns the shaded area: The syntax for the INNER JOIN in PostgreSQL is: SELECT columns PostgreSQL INNER JOINS return all rows from multiple tables where the join condition is met. Chances are, you've already written a statement that uses a PostgreSQL INNER JOIN. ![]()
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