SQL: SQL, copy data from one table to another

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One of those maintenance tasks: copying data from one table to another.

You can copy all elements from a table into another like this:

INSERT INTO some_table
SELECT * FROM other_table

Of course you can just select some if you want:

INSERT INTO some_table
SELECT * FROM other_table WHERE list=94

If the table you’re copying to has existing data, you might have primary key duplication issues.

To leave the primary key column empty to make the table auto-fill it with its auto increment, I selected all columns except the primary key:

INSERT INTO some_table (`age`, `name`, `email`)
SELECT `age`, `name`, `email` FROM other_table

In my case id was the primary key column, and I left it out.

Lessons in this unit:

0: Introduction
1: Using TablePlus
2: Create a Postgres database
3: Create a new table
4: Add data to a table
5: Query data with SELECT
6: Delete data from the database
7: Update data with UPDATE
8: Null constraints
9: Unique and primary keys
10: Updating a table structure
11: Joins
12: SQL Views
13: ▶︎ SQL, copy data from one table to another