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How do you prevent SQL injection in Node.js database access?

Q: How do you prevent SQL injection in Node.js database access?

**TL;DR.** **Never interpolate user input into SQL strings.** Use **parameterized / prepared statements** ( $1 , ? placeholders) so the driver sends the query and the data **separately** — the input is treated as a value, never as SQL, making injection impossible. ORMs and query builders parameterize by default. "…WHERE id=" + input ❌ injectable "…WHERE id=$1", [input] ✅ parameterized <path class='d-edge-accent' d='M222 106 H290' marker-end='ur

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Understand the problem

Parameterized queries vs string interpolation.

nodejssecuritysql-injectiondatabase

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Parameterized query with pg

// ❌ injectable
// db.query("SELECT * FROM users WHERE email = '" + email + "'");

// ✅ parameterized — input bound as a value
const { rows } = await db.query(
  'SELECT * FROM users WHERE email = $1 AND active = $2',
  [email, true],
);

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