1. Databases

2. Databases Database Searching Database Searching Definition: A database is any organized collection of data that can be retrieved using organized search procedures. Definition: A database is any organized collection of data that can be retrieved using organized search procedures. Phone books are databases of names, addresses and phone numbers. Phone books are databases of names, addresses and phone numbers. –Organized alphabetically and use an organized search procedure involving the alphabet to retrieve data. –Yellow pages organized by subject, then by alphabet.

3. Databases Database Searching Database Searching Computerized databases present new problems Computerized databases present new problems –C. databases are generally much larger than print ones. –There are few common conventions for organizing and searching, so every new database is a new experience. –Unlike a phone book or the old library card catalogue, you can’t really browse a database well. Computers, being inherently unintelligent, don’t always understand what you want.

4. Databases Database Searching Database Searching Case: Librarian found remnants of a search on a computerized periodical index database. Case: Librarian found remnants of a search on a computerized periodical index database. –Database had over 1,000,000 journal citations. –Searcher typed in keyword Johnson, resulting in 4,386 hits. –What was worse, the searcher had actually started pulling each of the 4,386 entries in turn, looking for the right one.

5. Databases Database Searching Database Searching For retrieving information from computer databases, there are two basic search tools. For retrieving information from computer databases, there are two basic search tools. –Controlled Vocabularies –Keywords

6. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies Most common controlled vocabulary system in North America is the Library of Congress Subject Headings system, used in most libraries. Most common controlled vocabulary system in North America is the Library of Congress Subject Headings system, used in most libraries. How did subject originate? headings How did subject originate? headings –Library of Congress (LC) predetermined the terms by which most things in the world would be called and organized these into alphabetical lists. –Some subject headings were easy: dogs are Dogs, sunflowers are Sunflowers.

7. LOCATIONCALL #STATUS Nichols Reference Z695.L685 2004 v.1 Z695.L685 2004 CHECK SHELF Nichols Reference Z695.L685 2004 v.2 Z695.L685 2004 CHECK SHELF Nichols Reference Z695.L685 2004 v.3 Z695.L685 2004 CHECK SHELF Nichols Reference Z695.L685 2004 v.4 Z695.L685 2004 CHECK SHELF Nichols Reference Z695.L685 2004 v.5 Z695.L685 2004 CHECK SHELF AuthorLibrary of Congress. Cataloging Policy and Support Office. TitleLibrary of Congress subject headings / prepared by the Cataloging Policy and Support Office, Library Services. Edition27th ed. ImprintWashington, DC. : Library of Congress, Cataloging Distribution Service, 2004. Descript5 v. ; 31 cm. Contentsv. 1. A-C -- v. 2. D-H -- v. 3. I-M -- v. 4. N-R -- v. 5. S-Z. Note"ISSN 1048-9711"--T.p. verso. SubjectSubject headings, Library of Congress. Subject headings. Alt authorLibrary of Congress. Cataloging Distribution Service

8. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies –Some were more difficult. –What do you call senior citizens? LC chose AGED. –TV faith healers are HEALERS IN MASS MEDIA. –Why? Because LC said so. –That’s the point with controlled vocabularies. –These vocabularies are created by people “out there” who then control them.

9. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies –Some were more difficult. –What do you call senior citizens? LC chose AGED. –TV faith healers are HEALERS IN MASS MEDIA. –Why? Because LC said so. –That’s the point with controlled vocabularies. –These vocabularies are created by people “out there” who then control them.

10. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies Rule #1: With controlled vocabularies, you have to use the subject terms provided by the system. No options are allowed. Rule #1: With controlled vocabularies, you have to use the subject terms provided by the system. No options are allowed. –Book titled Them TV Preachers may have the subject heading HEALERS IN MASS MEDIA. –Book called Active Seniors in Today’s World may be labeled with subject heading AGED. –Neither book had any of the actual words of the subject heading in its title.

11. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies Rule #2: The actual wording of the data record (book title or catalogue entry) is not important for controlled vocabularies. Subject headings are assigned on the basis of somebody’s judgment as to what the data is about. Rule #2: The actual wording of the data record (book title or catalogue entry) is not important for controlled vocabularies. Subject headings are assigned on the basis of somebody’s judgment as to what the data is about. Advantages: I have 5 books with following titles: Advantages: I have 5 books with following titles: –Terminal ChoicesChoosing Life or Death –EuthanasiaThe Practice of Death –The Right to Die

12. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies All are assigned subject heading: EUTHANASIA All are assigned subject heading: EUTHANASIA Presented with database to search, main problem is retrieval. Presented with database to search, main problem is retrieval. Controlled vocabularies the solution. Controlled vocabularies the solution. Typing word into the computer and getting back a book list regardless of the wordings of the actual titles. Typing word into the computer and getting back a book list regardless of the wordings of the actual titles. That is what controlled vocabulary is designed for. That is what controlled vocabulary is designed for.

13. Databases Database Searching—Controlled Vocabularies Database Searching—Controlled Vocabularies Rule #3: Use a controlled vocabulary as a search tool when you want a collection of data on the same subject regardless of what the data actually says about itself. Rule #3: Use a controlled vocabulary as a search tool when you want a collection of data on the same subject regardless of what the data actually says about itself. –Most libraries have an edition of the LC subject headings in print or a microfiche edition. –Many databases can be searched only by keyword. –The lack of a controlled vocabulary search option can be a disadvantage when all you want is a set of data on one subject regardless of what the date says about itself.

14. Databases Keywords Keywords Rule #1: With keyword searching, what you type is what you get. The computer cannot interpret your request or give you the next best solution. All it can do is identify the words you ask for and give you the related data. Rule #1: With keyword searching, what you type is what you get. The computer cannot interpret your request or give you the next best solution. All it can do is identify the words you ask for and give you the related data.

15. Databases Keywords: Boolean Searching Keywords: Boolean Searching A system to formulate searches where two or more terms are used. A system to formulate searches where two or more terms are used. The “OR” Command The “OR” Command –Want all information that has “cars” in it, but know that some people say “automobiles.” –I tell the computer to look for both words at the same time with the “OR” command. –In a situation in which I am searching for synonyms, I use the “OR” command.

16. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “OR” Command The “OR” Command –Another situation calling for an “or” search might be that in which two concepts are closely related, and you might expect data on either of them will be useful to you. –E.g., in search for “psychoanalysis,” you might be well advised to search as well for the father of psychoanalysis—Sigmund Freud. –With the “or” search, one typically gets lots of hits.

17. Databases Keywords: Boolean Searching Keywords: Boolean Searching Rule #2: An “or” search is usually for synonyms or for keywords that are already closely related. With it, you are trying to anticipate the various ways something might be described or approached. Rule #2: An “or” search is usually for synonyms or for keywords that are already closely related. With it, you are trying to anticipate the various ways something might be described or approached.

18. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “AND” Command The “AND” Command One of the most profitable uses of keywords is in combining topics to narrow down a search. One of the most profitable uses of keywords is in combining topics to narrow down a search. E.g., a LC subject heading might=“Mental Health—Religious Aspects” E.g., a LC subject heading might=“Mental Health—Religious Aspects” What if you wanted to look at information on relationship between prayer and mental health? What if you wanted to look at information on relationship between prayer and mental health? A subject heading might let you down, but a keyword would get you what you want. A subject heading might let you down, but a keyword would get you what you want.

19. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “AND” Command The “AND” Command –The formulated keyword search would look like prayer and mental or or Prayer and mental and health –A more complicated formula prayer and mental and (health or illness) –The data will have prayer and mental in it and in addition must have either health or illness in it.

20. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “AND” Command The “AND” Command Rule #3: A keyword “and” search is used to search for data that relates two topics or concepts together. The data found will show the effect of the relationship of these topics. Rule #3: A keyword “and” search is used to search for data that relates two topics or concepts together. The data found will show the effect of the relationship of these topics.

21. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “AND” Command The “AND” Command Rule #4: “And” searches will narrow or limit your topic. Thus you can expect that you will not get as many “hits” with an “and” search as with an “or” search. Rule #4: “And” searches will narrow or limit your topic. Thus you can expect that you will not get as many “hits” with an “and” search as with an “or” search. –Adding more “ands” simply guarantees fewer hits. –Outside of “or” searching, putting more keywords on the screen leads to fewer results.

22. Databases Keywords: Boolean Searching Keywords: Boolean Searching The “Not” Command The “Not” Command Back to looking for cars, the one type of car you’re not looking for is any car made in Europe. Back to looking for cars, the one type of car you’re not looking for is any car made in Europe. Formula=(cars or automobiles) not Europe* Formula=(cars or automobiles) not Europe* –Have added the “not” and have done a truncation on Europe (using an asterisk) so the computer could look for “Europe” and “European” with a single search.

23. Databases Keywords: Boolean Searching Keywords: Boolean Searching Exceptions Exceptions –Some databases want you to put your linking words in capital letters—OR AND NOT –In some databases you can do an “and” search simply by leaving a space between words, but other databases will see two words as a phrase where the two words have to be found together in that order. –Internet keyword searches often use + and – signs. –In some databases, “not” has to be expressed as “and not.”

24. Databases Keywords: Boolean Searching Keywords: Boolean Searching Exceptions Exceptions –Some databases ask you to put quotation marks around words that need to appear together. Complex Keyword Searches Complex Keyword Searches –Some databases allow you to build your own search with a grid arrangement that allows you to specify what words in what types of combinations you want to search. Some databases and some search engines are playing around with natural language searches; Boolean searches tend to be more precise. Some databases and some search engines are playing around with natural language searches; Boolean searches tend to be more precise.

25. Information Hierarchies –If I want to find my way through the information fog, I have to learn some theory about the way information is structured. –Define: ROCK “A hard object that comes out of the ground.” “A hard object that comes out of the ground.” “No, it is a verb.” “No, it is a verb.” “You’re both wrong. Rock is a kind of music.” “You’re both wrong. Rock is a kind of music.” –Words by themselves don’t really mean anything for certain. They only have a definite meaning when you put them in context.