Function embedding_coverage 

pub fn embedding_coverage(
    conn: &Connection,
    namespace: Option<&str>,
) -> Result<(u64, u64)>

#1598 — (total_rows, rows_with_embeddings) for the reembed dry-run plan, optionally namespace-filtered. COUNT(embedding) counts non-NULL values, so the missing count is the difference.

Errors

Returns the underlying SQLite error.