Sandbox

SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b6f4bc540ed7ce5b73e7be6d9984e77c6eec8eb401afdf17b45a0c5033add6e9' 
  AND token = 'Czf0gmtvWBkUvbGO2nuC8t63jyfGOhsX8zCagOAEzUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}