After INSERT and UPDATE, DELETE completes our core data manipulation trilogy. DELETE statements permanently remove rows from your table—there's no undo button!

Like our other operations, DELETE follows the same SQL engine pipeline: parsing, planning, optimization, and execution.

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What makes DELETE potentially more dangerous than INSERT or UPDATE?

The basic DELETE pattern is: DELETE FROM table WHERE condition. Notice there's no column list—DELETE removes entire rows, not individual values.

This removes all users over 65 completely from the table.

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Which users will remain in the table after this DELETE executes?

The WHERE clause is absolutely critical with DELETE. Without it, you delete EVERY row in your table!

DELETE FROM products; would empty your entire products table—probably not what you intended.

Always include WHERE unless you genuinely want to delete everything.

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Why might someone intentionally delete all rows from a table?

Before executing DELETE, always preview which rows will be affected by running a SELECT with the same WHERE clause first.

SELECT * FROM users WHERE age > 65; shows you exactly what DELETE FROM users WHERE age > 65; will remove.

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How does this preview strategy help prevent mistakes?