Céline Petit
PRO
3 days ago
Célinecountry asked

What happen if the table already exist but with different columns? CREATE TABLE IF NOT EXISTS Customers ( id int, first_name VARCHAR(50), last_name VARCHAR(50), age int, country VARCHAR(50) );

N
Expert
yesterday
Nisha Sharma answered

If the table already exists but the columns are different, CREATE TABLE IF NOT EXISTS won’t try to “fix” or update anything. It simply checks: does a table named Customers already exist? If yes, it stops right there.

So what this really means is:

  • No error is thrown

  • No changes are made

  • The existing table stays exactly as it is, even if your new CREATE TABLE statement has different columns

If you actually want to change the table’s structure (add/remove columns, change data types, etc.), you’d use something like ALTER TABLE, or you’d drop and recreate the table if that’s appropriate for your setup.

Hope that helps. Feel free to reach out if you have any more questions.

SQL
This question was asked as part of the Learn SQL Basics course.