SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a14be7349804e28c687f58091edb47af80bb16f229170694c7e5ac891efed99' 
  AND token = 'Ba5BnHxarxKjc/YjsjzeZPPh00Ph+QlQuYhXEPw1spE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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