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    <p>UUID stands for Universally Unique IDentifier. Most of the bits of a typical UUID are dedicated to the problem of making the identifiers <em>universally</em> unique, both in time and in the "space" of the internet. In fact there are a number of different UUID formats that address this problem in different ways, but they all depend on having a lot of bits (~128) for the UU characteristics. The <a href="http://en.wikipedia.org/wiki/Uuid" rel="nofollow">Wikipedia page</a> on UUIDs gives more details and has links to relevant standards and specifications.</p> <p>You seem to be asking if you can use a substring of a UUID. The answer is that if you do this you will probably end up with an identifier that doesn't have strong enough guarantees of uniqueness.</p> <p>If you want to generate identifiers for private purposes, they probably don't need to be universally unique. Your identifiers' uniqueness requirements (and other characteristics) will depend on the use to which you intend to put them, and without you telling us what they are, it is hard to suggest an appropriate solution. But here are some examples:</p> <ul> <li>For simple cases, a timestamp or some other monotonically increasing integer sequence will be sufficient. </li> <li>If you want weak or stronger non-guessability you could use some kind of random or pseudo-random number generator. </li> <li>If you need to generate these numbers at multiple places, either incorporate the location into the id, or split the id-space into subspaces in some way.</li> </ul> <p>It is also necessary to do your sums on the likely rate of identifier generation / use, and consider what happens when your id generator runs out. (Is wrap-around acceptable? Can you reclaim and reissue ids that are no longer used? Does your chosen id representation allow you to expand / extend the id space?)</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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