SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ea7daca7780f62473590f735452f9715be03d349e9cd13fc12b02e574ac8a9a' 
  AND token = 'Z4PVbQKafKnZmGhmBacmV12o8WUv563f/apACOniRfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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