# validate_composite_indexes_tx_rids_and_op_index · FT4 Rell API · Chromia Docs (concept)

> function validate_ composite_ indexes_ tx_ rids_ and_ op_ index(transaction_ rids: list<byte_ array>?, op_ index: integer?) Throws INVALID FILTER if the li

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.utils/validate_composite_indexes_tx_rids_and_op_index/

FUNCTION

# validate\_composite\_indexes\_tx\_rids\_and\_op\_index

```signature
function validate_composite_indexes_tx_rids_and_op_index(transaction_rids: list<byte_array>?, op_index: integer?)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/utils/utils.rell#lines-273)

Throws `INVALID FILTER` if the list of `transaction_rids` is not empty, but `op_index` is not specified or
if `op_index` is specified, but `transaction_rids` is empty

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.utils/validate_composite_indexes_tx_rids_and_op_index.html)Generated API reference, mirrored from the live docs