Yesterday in FORT 120 we started looking at Microsoft Access, a relational database management system. It has similarities with Excel, the spreadsheet solution. This raises the question, why learn both programs and when should one be used over another.
At first glance there are similarities. Both store data in tables of rows and columns. Both perform calculations and have form and report-writing utilities. However, there is a big difference.
In an interesting article on the Microsoft web site Emma Nelson pinpoints the big difference. Excel is best when all the data fits into a single table (known as a flat file). When the data should be divided into multiple tables that relate to each other through common fields, Access can best handle the job. In a relational database the data is divided into multiple tables to make storage more efficient and search quicker. Access has all the tools needed to manage a relational database.
Borrowing from the Nelson article, use Access when you:
- Require a relational database (multiple tables) to store your data.
- May need to add more tables in the future to an originally flat or non-relational data set.
- Have a very large amount of data (thousands of entries).
- Have data that is mostly of the long text string type (not numbers or defined as numbers).
- Rely on multiple external databases to derive and analyze the data you need.
- Need to maintain constant connectivity to a large external database such as one built with Microsoft SQL Server.
- Want to run complex queries.
- Have many people working in the database and want robust options to expose that data for updating.
And use Excel when you:
- Require a flat or non-relational view of your data (you do not need a relational database with multiple tables). This is especially true if that data is mostly numeric–for example, if you want to maintain a financial budget for a given year.
- Want to run primarily calculations and statistical comparisons on your data — for example, if you want to show a cost/benefit analysis in your company’s budget.
- Know your dataset is manageable in size (no more than 15,000 rows).
In Geographic Information Systems (GIS) we combine geographic data with attribute data. This requires multiple complex data tables that use a relational database tools. In fact the geodatabases used in ArcGIS desktop use Access databases by default. When you make a map with data in ArcGIS you are, in effect, using a relational database.
Posted in FORT 120
Tagged databases, GIS
One of my favorite trees in Africa is the Nï¿½rï¿½ (Parkia biglobosa). This species is so useful that it has been preserved and cultivated around the villages and throughout the landscapes of west African countries. Below is a superb specimen outside the Environmental Education Center in Kinkon, Guinea in the Fouta Jalon Highlands, where I was visiting in December, 2006.
Another name is the African locust bean tree. The nï¿½rï¿½ is a legume, and can therefore fix nitrogen. A more important use is to ferment the seeds to make a cooking condiment called soumbala, that is prized in local cooking around the region.
This pictures shows the flower pods, which are bright red when mature.
This photo found on Flickr shows soumbala being processed and presented in the market.
Family at the market Originally uploaded by v3ronique.
The caption says: “Little girl stays very close to her mother while she is making ‘soumbala’ or “Maggi” at the market. They are made of fermented seeds rolled into a ball and fried. “
This USDA Germplasm Resources Information Network article has botanical information.
This article, in pdf format, has general information about nere and its nursery requirements.
Here is a presentation I gave recently on using GPS. online maps, and blogs for forestry work.
The Mira Lloydd Dock slide collection is a fascinating view of trees, other plants, and scenery from the late nineteenth century. Dock used these slides in numerous lectures promoting conservation around Pennsylvania. She also used them in guest lectures to forestry students at Mont Alto in the first years of the school. Follow this link to see a review I wrote shortly after the slides web site was created.
While discussing Microsoft Word with my computer class this afternoon, I asked how you should indent the first line of a paragraph. This was a trick question of course. Virtually all the students said that you should press the Tab key, since this is what they were taught and what they have always done.
However, tabbing is really bad form. The best practice is to format the paragraph to include indents. That way when you start a new paragraph it will retain the indentation and all the formatting of the previous paragraph.
Better yet, create a style for the type of paragraph you need. Then when you change that style it will change globally throughout the document. There is nothing more tedious than having to go paragraph by paragraph through a long document to change the line spacing or any other formatting option.
I liked the statement by Woody Leonhard in one of his Office books, that the best thing to do with the Tab key when using Word is to prise it off the keyboard so that it can do no more harm! Of course that would leave a hole in your keyboard and prevent you from doing all the useful things the Tab key can do in other applications. Also, they might not approve of it in the computer labs.
Posted in FORT 120
Forest technology students often need images for reports, presentations, and web pages. Sometimes it’s hard to find a picture that you can legally use due to copyright issues. One great source of images is Forestry Images. It seems to be housed at the University of Georgia. Most images can be downloaded in a variety of sizes. For the larger sized you need to sign up for a free membership.
Then all you need to do is cite the image according to the recommendations on the page. For example, this black walnut image:
Richard Webb, Self-employed horticulurist, Bugwood.org
Today we looked at Google Docs. Another solution is Open Office, which just came out with version 3.0 recently. It is a full featured office suite and best of all it is free. Check it out at http://www.openoffice.org. Be aware that it is a 140 megabyte plus download.
And here is a helpful blog with tips and hints for using Open Office. Open Office will work with many operating systems, including Macintosh.