SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e25bd6f16d148ae47761a02c259d43f393b65e9664cf357cd9f7e5723ab3497c' 
  AND token = 'K8Jq0E0UVSYRgZuDPqgV3zmaOtjyCMvAKlSNV6m5m68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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