SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c67866f6ba8ce67d57eacb56b63693d8dcde4347b23a848afb9ea88d720ee78' 
  AND token = 'bAZwN01h/e79QO/rfrtcQpV/T4lZvCjeByxC1sCO8Jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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