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Databases Modifying Data with SQL Adding Data to a Database Adding a Row to a Table

INSERT INTO not working

When typing the exact command from the video, I keep getting the following error:

Error: UNIQUE constraint failed:

Can someone please help with this?

Fletcher Henneman
Fletcher Henneman
3,130 Points

This may mean that you already have a row with the same ID/values. Try using REPLACE INTO.

Try following the answer on this question. Use REPLACE INTO if it is a duplicate Stack Overflow

1 Answer

Brett Phillips
Brett Phillips
7,004 Points

It seems in SQL Playground this item already exists in the database. The error gives the clue that the primary ID of 16 already exists. You cannot have duplicate Primary Keys, which is why it's complaining that the "UNIQUE constraint failed".

The easiest way to check is to do a select to see for yourself: SELECT * FROM books;