Definition of indexing, datatype configuration, and DBMS for SHA3-256 hashes
SHA3-256 is 256bits. That's 32 bytes.


Don't store it as TEXT any form, or it'll be 256 bytes (8x the size).
I would store it as inline binary if your database supports it because I doubt anything it's going to have a data type for a 32 byte data type (which nothing uses except AVX2).


On indexing, any HASH index would work if your database provides it.

From PostgreSQL,

CREATE DOMAIN sha3_256 AS bytea;

CREATE TABLE datastore (
  id     int  PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
  myhash sha3_256
);

CREATE INDEX ON datastore USING HASH (myhash);

INSERT INTO datastore (id,myhash) VALUES
  (1, decode('36f028580bb02cc8272a9a020f4200e346e276ae664e45ee80745574e2f5ab80', 'hex'));




As a special optimization you could store it as two UUIDs. Though I probably wouldn't bother.