6.4: Choosing fields
- Page ID
- 65093
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)What is a field? A database is made up of records and the records are made up of fields. To visualize a database, think of a blank form, for example, a form for an academic record. It has blank lines for the student’s name, school ID number, the classes taken, the semesters in which they were taken and grades. Those are fields. Your institution’s student database is made up of thousands of these records: one for each student. Each of those records has all of the fields. When your institutions knows your name and wants your record, they will ask the database to look at every single record, but only at the names of the students until it finds your name in the name field. Then your whole record can be pulled up from just your name. If, on the other hand, they only have your ID number, they will ask the database to look at every record of every student, but only look at the ID numbers. They do this by typing your ID number into the search field called ID number. Then your whole record can be pulled up from just typing in your number.
Think of contacts in a cell phone. Every time you add a new person to your contact list, you create a record for that person. To create the record, you fill in the fields: name, phone number, address and so on. You create a record for each of your contacts in your phone by filling out the fields. So Mom has a record, best friend has a record and your boss has a record in the database you created on your phone. And fields hold the information that we are after. When you get an incoming call, the phone searches the number field and tells you your friend is calling. When you place a call by typing in your friend’s name, the database searches all of the names for your friend’s and then moves to the number field and dials it for you. Also notice that the database does not have Mom, best friend and your boss in it. Rather, the database has records for/about, Mom, friend and boss. This distinction will come in handy later.
The same principle applies to library databases. Notice in databases there is often a way to search author, title, keyword and other options. These (author, title, keyword …) are called fields and you are doing field searching when you choose one of them. Most of the time, this is not part of the basic search, but is available in the advanced search. You can see now how databases are made up of records. Records are made up of fields. And fields hold the information we search and are seeking. (See the search screen examples at the end of 6E.)
The field(s) you choose to use is dependent upon what information you have. If you know the author and title, you would choose the author and title fields (See 6I for known item searching). If you are looking for information on a topic, you use a variety of fields as discussed in 6E below.