How to encrypt/decrypt a dynamic SQL query in Golang with a fixed-size encrypted result?

I have a Golang application where I dynamically generate SQL queries based on struct comparisons, the data type of this results is a string. Like:

"SELECT id FROM table WHERE column_a = value_a AND column_b IN (value_b, value_c)"

The WHERE clause will be dynamic, we can have n conditions.

For security purposes, I want to encrypt the query result to store it in a database, and later I need to decrypt it for a execution in a job process.

I would like that the encryption produces a fixed-size result to ensure consistency in the database, and also to prevent an error if the encrypted result is too large to save in the database, for example if I have a limit of 255 characters, error reference: SQL Error 1406 (Data too long).

I tried with this example https://go.dev/play/p/VXD0j_DuycG, but the result increases in size if the input is longer.

Is it possible to achieve? Someone knows a guidance or documentation that could be helpful for this case?

Any guidance or documentation on how to approach this problem would be helpful, thanks!

Solution

Even if you only use procedures, security issues are largely resolved.

example...

delimiter //
CREATE OR REPLACE PROCEDURE Something(vals JSON)
BEGIN
    SELECT id
    FROM TABLE
    WHERE column_a = value_a AND json_contains(vals, column_b, '$');
END//

CALL Something('["value_b", "value_c"]');

If you want, you can also use json functions to do things like type checking.

and... I don't think it's desirable, but if you use the query in the above procedure, I think you can create a fixed-length query.