SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a7af0ef7a8b22f9fc9d70ed3eebae8ad2b4b03a9244fc07434cf4aefa96be9e' 
  AND token = 'TNgJRoIjNjpYOPdg2jCPCrbEJglgdp4NYYN73L5n/nU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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