SQL INSERT INTO SELECT

 The INSERT INTO SELECT statement in SQL allows you to insert data into a table from another table (or the same table). The SELECT query retrieves the data, and the INSERT INTO statement adds it to the target table.

Here’s the basic syntax:

INSERT INTO target_table (column1, column2, column3, ...)
SELECT column1, column2, column3, ...
FROM source_table
WHERE condition;

Explanation:

• target_table: The table where the data will be inserted.
• source_table: The table from which data will be selected.
• The column1, column2, ... should match between the target_table and the source_table in both order and type.
• WHERE condition is optional. It filters the rows from source_table that are to be inserted.

Example:

Suppose you have two tables: employees and new_employees. You want to copy employee data from new_employees into the employees table.

INSERT INTO employees (id, first_name, last_name, hire_date)
SELECT id, first_name, last_name, hire_date
FROM new_employees
WHERE hire_date > '2023-01-01';

This will insert all rows from new_employees where the hire_date is after January 1, 2023, into the employees table.

Let me know if you need more examples or further explanation!