Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fb7b55b7f3a8c1d15266766c012876f73718575ba75f4c1e871991bc4cf88c8' 
  AND token = '93zUpnwEznLR1IXEbKbaiI1zUt/RbP9/qMyO+znp+EQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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