Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebbda919aca75a46f1394be213959b1cd9da47bd781a1c3e71afead68f193458' 
  AND token = 'w7bDV5Nk5vlVDAKEVJdxP4aaCfCY7+EKSYqaMQl1c3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}