I have a query like

SELECT
patient_id, patient_name
FROM
patient_details_tbl
WHERE
date(generated_time) between ‘2024-01-01’ and ‘2024-04-30’;

I know if i simply create index on generated_time column then it wont work if we query with date(generated_time).

In oracle, we have a functional based index which creates in direct way for this kind of column.

But, How to create functional based index in INFORMIX to achieve this

CREATE INDEX idx_pdt_gen_time ON patient_details_tbl(date(generated_time)) ONLINE;

Kindly Help.

Please give me the code to achieve this in Informix