Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82045e3f0d3cb18d5ec021479f5dabd836e509e482c5053001c6f5fe9a09dc50' 
  AND token = 'YWrksBXs7vtH8DwSy0gi6sr+AwyL/GUv6Qi6Rbk2+GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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