What it does

Flags Drizzle query expressions (db.select, db.insert, db.update, db.delete) that appear inside for, while, do...while, for...of, or for...in loops.

Why it matters

Running a database query inside a loop triggers N+1 round-trips to the database. Batching the query outside the loop reduces latency and database load.

How it works

Pulsar checks the AST position of every Drizzle query expression. If the query is inside a for, while, do...while, for...of, or for...in body, the rule fires.

When to disable

Disable this rule when you intentionally query inside a loop with a small, fixed iteration count (e.g., < 5) and the query pattern is unavoidable.

Examples

for (const id of ids) {
  const user = await db.select().from(users).where(eq(users.id, id)); 
}

const results = await db.select().from(users).where(inArray(users.id, ids));