What does join on mean in sql

JOIN ON is a syntax for joining tables in SQL. It combines rows in different tables based on common columns and is used to: 1. Combine related table data; 2. Retrieve cross-table information; 3. Update or delete cross-table data.

The meaning of JOIN ON in SQL

JOIN ON is a way to join two or more tables in a SQL query A grammatical structure. It allows us to group rows from different tables together based on common columns.

Syntax

SELECT column_list
FROM table1
JOIN table2
ON table1.column_name = table2.column_name;

Where:

• column_list Specifies the columns to be retrieved from the query.
• table1 and table2 are the tables to be joined.
• column_name is the matching column name in the two tables.

Function

JOIN ON is used to match rows from two tables together based on specified conditions. When the join condition is met, it creates a row containing the corresponding data from both tables.

JOIN ON is usually used to:

• Combine data from related tables, such as the customer table and the order table.
• Retrieve specific information from multiple tables, such as product sales records.
• Update or delete data across multiple tables.

Example

The following query uses customers table and orders table using customer_id Columns concatenated:

SELECT *
FROM customers
JOIN orders
ON customers.customer_id = orders.customer_id;

This will return a table with information for each customer and all of their orders.

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