pub const KEY_IDENTITY_LIMIT: DocId = _; // 4_611_686_018_427_387_904u64Expand description
A table whose single primary-key column is an integer names each row whose key lies in 0..KEY_IDENTITY_LIMIT by the document identity equal to the key, so a key lookup reads that one identity. Its other rows, with negative keys or keys at or above the limit, take identities the table generates at or above the limit, where no key value names one; a key lookup reaches them through the key’s index.