SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce92675ff064a6e10ad5a571a61c7e430b198d83ce2796a3af51315edb1a73c5' 
  AND token = 'N1ZzxprlimhBe9/AAtZVlNDnzzPHJIvnxDA3yRia06k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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