SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2dd94497ef791a5e41c5acf1b50d50be4493a917eafc0614f6eec769226a8c90' 
  AND token = 'FBFO+B6Mh/Gz5mHRW0eHWVgqgHqmTCrx7AWQKfTK02g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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