Re: “CACHE INDEX” and “LOAD INDEX INTO CACHE”

[Rick James]

If the table is reloaded nightly, MyISAM should be fine. Furthermore, you could get rid of the PK and UNIQUE index since (presumably) you have validated that there are no dups:
INDEX(id, name)
INDEX(name, id)
Then the SELECTs would touch only the indexes.

Here is a way to reload the table with minimal downtime:
CREATE TABLE new ...
INSERT INTO new ...
RENAME TABLE dict TO old, new TO dict;
DROP TABLE old.
The only blockage with be in the RENAME, which is essentially instantaneous.
I don't know if the INSERTs would have sufficiently primed the key_buffer so that no further LOAD CACHE would be needed.