Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc4327b71b6ea05f71480e9cdc3101fb384b30caecb32e21fba5f56ebff61bf0' 
  AND token = '9vRh+5NoXv+jOS7m9Cc5vqSHwC+qRKPOvxrjr93L2Qk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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