# LDC-Q3001 — A package computation needs an explicit row cap

## What it means

Running a package over a case inside a query can produce any number of
rows, and the engine never assumes how many the caller is prepared to
read. Every query that declares such a computation must also state the
cap on produced rows up front. Without that cap the computation never
starts, and the engine asks for it instead of running unbounded.

Re-run the query with an explicit cap on produced rows. The computation
itself stays as written.

## Example

```lawql
let m = eval("demo.diagnostics", "case.json") from r in rules select r
```

## Fix

```lawql
from r in rules select r
```

## Engine message

The engine reports this in its own wording:

```text
LDC-Q3001: eval() requires an explicit --limit.
```

## Related

- [Questions to the engine](/constructs/queries/) — how a query runs a package over a case.
- [LDC-Q2002](/diagnostics/LDC-Q2002/) — when the computation itself is undeclared.