Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5a968a006e531ee615533d2bd2a21f310a5ca06ff6ce920bf87343e479be6ac' 
  AND token = 'jehdI+d8OSXeCluhYazdhtFHv5ncpQfQNPByamDAnQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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