With SQL, you can copy information from one table into another.
The INSERT INTO SELECT statement copies data from one table and inserts it into an existing table.
The SQL INSERT INTO SELECT Statement
The INSERT INTO SELECT statement selects data from one table and inserts it into an existing table. Any existing rows in the target table are unaffected.
SQL INSERT INTO SELECT Syntax
We can copy all columns from one table to another, existing table:
INSERT INTO table2 SELECT * FROM table1;
Or we can copy only the columns we want to into another, existing table:
INSERT INTO table2 (column_name(s)) SELECT column_name(s) FROM table1;
Example
INSERT INTO Customers (CustomerName, Country) SELECT SupplierName, Country FROM Suppliers;
or
INSERT INTO Customers (CustomerName, Country) SELECT SupplierName, Country FROM Suppliers WHERE Country='Germany';