How to join one to many tables in oracle database?

by lindsey.homenick , in category: MySQL , 6 months ago

How to join one to many tables in oracle database?

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1 answer

by haylee.mertz , 6 months ago

@lindsey.homenick 

To join multiple tables in Oracle database, you can use the SQL JOIN clause. Here's an example of how you can join multiple tables with a one-to-many relationship:


Let's say you have two tables, Employees and Departments. Each department can have multiple employees. You want to retrieve a list of employees along with their department information.


Here's SQL query to achieve this:

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SELECT Employees.employee_id, Employees.employee_name, Departments.department_name
FROM Employees
JOIN Departments ON Employees.department_id = Departments.department_id;


In this query:

  • We are selecting the employee_id and employee_name columns from the Employees table and the department_name column from the Departments table.
  • We are using the JOIN clause to join the Employees table with the Departments table based on the department_id column which is common between the two tables.


This query will return a list of employees along with their corresponding department information. You can also add additional conditions, sorting, or grouping to further refine your query based on your requirements.