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Databases

Posted by Matt Caminiti
Matt Caminiti
3,466 Points

Using INSERT INTO

Trying to copy data from one column in a table to another (placing foreign key values) using "INSERT INTO". It's successful but just creates all new rows with everything null except my foreign key values. Is there a way to tell the database to start inserting this information at a certain point?

Hope this makes sense.

2 Answers

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

It's normal for unnamed columns to have null after insert.

Your insert statement must cover more than just the one column if you want them to not be null. For a complete copy, you might try something like this:

INSERT INTO new_table SELECT * FROM old_table;

On the other hand, if you already have rows with nulls and want to fix that, it's no longer an INSERT but an UPDATE operation.

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

If I understand what you are trying to do, it is not normal to copy all the fields from one table to another. Only the foreign key is used as a reference to the row in the other table. When you make a query you will retrieve data from the first table using a JOIN between the two tables on the foreign key id.