Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6c0686917f2932089867f6ad7b40e43a7911dd03256384a39a3a75a17537f2f' 
  AND token = 'oEzgKYnNBHWa4bdLwDUZKqqqanszyr5FfWyRc3LlA3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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