For Oracle Database How to find when the row was inserted? (timestamp)
How to find out when an Oracle table was updated the last time
$-1$ is a quadratic residue modulo $p$ if and only if $p\equiv 1\pmod{4}$ I came across this problem and I believe Lagrange's theorem is the key to its solution.  The question is:     Let $p$ be an odd prime. Prove that there is some integer $x$ such that $x^2 \equiv −1 \pmod p$ if and only if $p \equiv 1 \pmod 4$.   I appreciate any help.  Thanks. Google results for sponsee have scattered definitions in unreliable sources, so it does not appear that is a real word. I'm looking for something similar, a single word.  The specific context is a social group membership application where new members must be sponsored (as in definition 2, here - "one who assumes responsibility for some other person or thing") by existing members. I am looking for a single word to describe the target of such a sponsorship. I am about to sponsor a fraternity, but I would like to have a more general word for what I'm sponsoring. Next time, the fraternity could well be a study club, or something else.  Therefore, what is the sponsored party also called? E.g. if I sponsor somebody, that person is my __? Does anyone know what this probability question is asking? Who did Khan get his Starfleet insignia from? How to design partitions for SSHD? Using a wi-fi and an ethernet connection at the same time thus having more bandwidth? I need to reset my password. I have followed these steps:    However, then I go to "root" or "netroot" recovery options, it tells me:  Give root password for maintenance (or type Control-D to continue)   Clearly, I do not know the root password. If I type CTRL+D, I return to the list of options. From  I read:  Under chapter 'The Other Way':  4. Highlight the line that begins kernel and press 'e' to edit`   But in the grub configuration file I have no line that starts with kernel. Only:  setparams 'Ubuntu...' recordfail set gxfpayload... insmod part_msdos insmod ext2 set root=... search --no-floppy... linux /boot/vmlinuz-2.6.38... initrd /boot/initrd.img-2.6....   Those are all lines in my GRUB. Which line should I edit? Or is there another way to reset my password? What are the prerequisites for studying mathematical logic? I am looking to study mathematical logic, however, I find that introductory books are very daunting, which kind of disheartens me. You see, slowly but surely, I started to realize that the maths which I have learned did not just pop out of thin air, but is a collection of systems, which must of been developed via some other system, i.e, maths did not develop itself.  So I began to look into the origins of mathematics, and read that it was developed via a type of logic, which exists sort of by 'default', via a set of axioms, and then of course I looked up the definition of axioms.   So given that I'd be studying a type of logic whose origins are self evident axioms, naturally I believed there would be no prerequisites. However, in looking up mathematical logic, I have come across things such as Boolean algebra, sets, first order logic, some other type of logic, called 'traditional logic', as well as references to a sort of calculus, though not in a mathematical sense, I think.  So all in all, I am trying to develop a type of mental spider web, and I am trying to find out the strands which lye at the absolute bounds so that I may learn this mystique logic. Though I have no idea where to start.  Side note: This is the book I have started reading:   Credit goes to Wolfgang Rautenberg. Product rule intuition Can anyone think of an intuitive explanation of the product rule? I'm not asking for a derivation. To me it seems like quite an un-untuitive result, as apposed to the chain-rule (which is ironically harder to derive). What are some CD ripping programs for Ubuntu? Can you list the Pros? What are the Cons? For each program there should be a screenshot, sources to install, and instructions to install and use. Passing a varible from jQuery to PHP Using Ubuntu 11.10, how do I format an external or USB drive? I don't find an option to 'format' when I right click. In the new version, the drives don't come up on the desktop, but instead come on the Launcher. Can you cast a 9th level spell if your multiclass spell slots have 9th level spell slots? What's the name of each pseudo-rectangle in a spherical surface? How to access the grub boot menu in order to generate bootchart? I am running Ubuntu Gnome 15.04, and I want to generate a bootchart to help me diagnose some system problems. However in  it says:    So how do I access the grub boot menu in order to append this text? And just to be clear, how should the line look once I have appended the necessary text? Also, is grub already installed for I don't appear to have either or these packages: grub or grub2?    OS Information:  No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 15.04 Release:    15.04 Codename:   vivid Virtualbox Kernel driver not installed I tried to use my Virtual Box and this is the error I received - (I just updated to the new Ubuntu also) and I am VERY new at this Linux OS.     Kernel driver not installed (rc=-1908)      The VirtualBox Linux kernel driver (vboxdrv) is either not loaded or   there is a permission problem with /dev/vboxdrv. Please reinstall the   kernel module by executing      '/etc/init.d/vboxdrv setup'      as root. Users of Ubuntu, Fedora or Mandriva should install the DKMS   package first. This package keeps track of Linux kernel changes and   recompiles the vboxdrv kernel module if necessary. Recommended visualization libraries for standalone applications Do I need an airport transit visa for Dublin, Ireland en route to the UK? How to show that $\mathbb{Q}$ is not $G_\delta$ I read a section of a book and it made mention of the set of rationals not being a $G_\delta$. However, it gave no proof. I read on  about using contradiction, but it made use of the Baire category theorem, which is unfamiliar to me. I was wondering if anyone could offer me a different proof; perhaps using the fact that the complement of $G_\delta$ is $F_\sigma$.  Thanks. Submitting form elements with the same name