Left Join is a keyword, which is used to select all rows from the left table and also the matched values between the two tables.
The Left Join in SQL basically returns all records from the left table and the matched records from the right tables. For example, let’s say, we have two tables, Table A and Table B. When Left Join is applied on these two tables, all records from Table A and only the matched records from Table B will be displayed.
SELECT columns FROM table1 name LEFT JOIN table2 name ON table1.coumn_x = table2.column_y;
where SELECT, LEFT JOIN, and ON are the keywords, columns is the list of columns, table1 is the first table and table2 is the second table, and column_x and column_y are the columns for performing the left join, followed by a semicolon.
Let’s apply Left Join to two tables, the employee table and the department table
Select employee.e_name, employee.e_dept, department.d_name, department.d_location from employee LEFT JOIN department ON employee.e_dept = department.d_name;
After writing the query, click on the execute button to check for errors. Once the query is executed, a message appears like ‘Commands completed successfully’
This brings us to the end of this Left Join in SQL tutorial section Go ahead and link the tables from your database to get a better insight of your data. In the next tutorial section, we will discuss on the Right Join.Previous Next
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