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1 | |
Since the objective of physical database design is to minimize the combined demand of all applications using the database, it is usually necessary to balance the sometimes conflicting needs of both retrieval and update applications. |
| | A) | True |
| | B) | False |
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2 | |
In a hash file, when a collision occurs and there is no free space in the physical record to be written to, the logical record is written to the end of the file with a pointer to it. |
| | A) | True |
| | B) | False |
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3 | |
In a Btree file structure, only the pointers to the data records are stored in that file; the actual data records are always stored in a different physical file. |
| | A) | True |
| | B) | False |
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4 | |
In index matching on composite indexes, columns are matched left to right, and matching stops when the next column in the index does not match. |
| | A) | True |
| | B) | False |
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5 | |
In the query transformation task of database language translation, a query that has already been analyzed for syntax and semantics errors is transformed into a relational algebra query. |
| | A) | True |
| | B) | False |
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6 | |
Each operation in an access plan has a corresponding cost formula that estimates the physical record accesses and CPU operations, and these formulas are used by the query optimization component to evaluate different access plans. |
| | A) | True |
| | B) | False |
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7 | |
Most optimization components assume that combinations of columns are statistically independent, therefore most DBMSs do not maintain statistics on column combinations. |
| | A) | True |
| | B) | False |
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8 | |
Index selection involves choices about two kinds of indexes, Btree and bitmap. |
| | A) | True |
| | B) | False |
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9 | |
In selecting an index, a column used in highly selective range conditions is a good choice for a nonclustering index. |
| | A) | True |
| | B) | False |
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10 | |
To implement parallel processing capabilities usually requires upgrading to a more expensive DBMS, but no additional hardware is usually needed. |
| | A) | True |
| | B) | False |
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