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CS 101 Attendance. 3/20/2013. This table has how many records?. 3 4 12 24. Each record in this table has how many fields?. 3 4 12 24. An appropriate use for a database management system is. The text for your research paper The budget for next month The names of all your MP3’s
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CS 101 Attendance 3/20/2013
This table has how many records? • 3 • 4 • 12 • 24
Each record in this table has how many fields? • 3 • 4 • 12 • 24
An appropriate use for a database management system is • The text for your research paper • The budget for next month • The names of all your MP3’s • The classes you are taking this semester
An integer is different from a single-precision number in that • Integers are not allowed in databases • Single-precision numbers can have fractions in them, integers cannot • Integers take up less space to store than a single-precision number • Integers are obsolete, single-precision numbers are used instead
A database system used for e-commerce is • Oracle • MS Access • Lotus 1-2-3 • mySQL • 1 and 4
A query is • not allowed in databases • A rule that all data must follow • A request for records that match a given pattern • Only allowed on number fields
What does it mean for two users to access a database concurrently? • They are on the same computer • They are using the same DBMS at the same time • They are reading from the same database file across a network • It's impossible
If you wanted to ask the query, "who are the customers from Kentucky OR Virginia?" • You must ask for one state at a time • You put the criteria on the same line of the query • You put the criteria on different lines • Either 2 or 3 will work
What sort the following table is based on? • This is sorted by Size within Color • This is sorted by Color within Size • It could be either
Two users accessing a database file concurrently • is impossible, only one user per file can be done • is ok as long as they are just READING • is prevented in MS Access by a “lock” file • is possible and perfectly ok for any file
Relationships between tables are • represented by matching values in key fields • are stored by pointers behind the scenes • are not possible • one-to-one, one-to-many or many-to-many • more than one of the above are correct
Referential integrity • means the DBMS keeps the relationships between tables consistent • means you may not be able to delete a record because it is involved in a relationship • is the same thing as data validation • more than one of these answers is right