SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ebd45b84964e84a61c3244f037b746947dab30961321e4499495261747a51c2' 
  AND token = 'ZM0Ypst1IFDWh7RKK+RnAPyx8Rk0F1F5mqSKfFZ/JgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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