SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '471dd873eb470fd2474681b22aa075e833eec3cc66058a67133b9dba5021ffe2' 
  AND token = 'qmA22vPnhMFz2+nvSmPndNFx/KljeM8lgJXjcWzgOro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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