what are "Meta-Data design principles"?

Question

I'm looking at a job description that I'm considering applying for, and one of the requirements listed is "Familiar with Meta-Data design principles".

Can some give a brief explanation? I'm probably familiar with the concept, but I've never heard that terminology before.

I did Google to find more info, but didn't get good results. Except for this white paper titled Metadata Principles and Practicalities. It was a little heavy, and I was hoping to find a quick explanation.

---

Additional Note: Thanks for all the answers so far. They've been very good. I wanted to clarify that I'm familiar with what metadata is, but I've just never heard of "metadata design principles". What sort of design principles are there for metadata have? Is this a large enough topic for a book? for a pamphlet? As Robert Harvey points out, it sounds like a nebulous term invented by someone in HR.

Answer 1

I'll bet it means "design principles include being driven by meta-data".

There aren't many design principles for meta-data -- it's usually given by your tools.

However, some organizations want to use meta-data as a key part of application software specification, construction and operation.

If they want someone who's design principles include using meta-data heavily, then it might come out as a phrase like "meta-data design principles".

But, before I said anything, I'd ask them what they think they meant by this.

Answer 2

Essentially, that would be the design of data about data; that is, characterizing data with additional data. Metadata is data about data; where data can be the orders that you get for a given item, the metadata about it can be things like how MANY orders you got, etc. Proper metadata design involves understanding what types of information is likely to be useful and interesting about whatever data you're analyzing, and recognizing how to most appropriately track and capture it.

For example, the number of sales of a given book in a particular day may be useful; not necessarily so the number of sales of the same book in a given minute. Likewise, the number of sales in a given year may be less useful than sales by month, etc. In this example, it's granularity, but metadata design can involve many other things; perhaps geographic distribution of sales is important, as another example.

Answer 3

The phrase, "Familiar with metadata design principles," sounds suspiciously like one of those nebulous phrases invented by an HR department that has no clue what they are talking about. However, I'll take a stab at it.

Metadata is data that enhances other data by describing the properties or characteristics of that other data.

Examples:

In the following tag:

<a href="http://google.com"&gt;Link to Google</a>

the href descriptor is metadata because it "decorates," or further describes, the link. It is a property of the link. In general all HTML attributes are metadata.

A C# attribute is metadata. Microsoft calls attributes "a way to associate declarative information with a class."

[System.Serializable]
public class SampleClass
{
    // Objects of this type can be serialized.
}

In a database table, the value contained in the Address field of a record:

12345 Main Street

is just data, but the field's definition in the database:

Type: Text
Length: 50

is metadata.

In an MP3 file, the audio is just data, but the MP3 tags such as Author, Title, and Bitrate are metadata.

XML is data, XSD is metadata. XSD can be used to express a set of rules to which an XML document must conform in order to be considered 'valid'.

The number of sales of a particular book in a given period is not metadata for the book, because it does not further describe the book itself, only its sales. However, the Author, Title, and number of pages of a book is metadata for that book (as is the ISBN).

There. Now you know all about "Metadata Design Principles."