Questions about database representaiton
Recently I am reading a paper, and here the author gives the way of database representation.
I feel confused. Could someone give me an example of the so-called universe and histograms? My thought is that suppose a database has columns a b c, and |X| equals to 3. Each attribute is a type i. But how about ab ac bc abc? Will all counts of type i sum up to the size of database? Is $||x||_1$ the record number of the database(the size)? And how large is |X|?
definition computer-science
asked Nov 27 at 2:42
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Recently I am reading a paper, and here the author gives the way of database representation.
I feel confused. Could someone give me an example of the so-called universe and histograms? My thought is that suppose a database has columns a b c, and |X| equals to 3. Each attribute is a type i. But how about ab ac bc abc? Will all counts of type i sum up to the size of database? Is $||x||_1$ the record number of the database(the size)? And how large is |X|?
definition computer-science
asked Nov 27 at 2:42
Sooner
197
add a comment |
Recently I am reading a paper, and here the author gives the way of database representation.
I feel confused. Could someone give me an example of the so-called universe and histograms? My thought is that suppose a database has columns a b c, and |X| equals to 3. Each attribute is a type i. But how about ab ac bc abc? Will all counts of type i sum up to the size of database? Is $||x||_1$ the record number of the database(the size)? And how large is |X|?
definition computer-science
asked Nov 27 at 2:42
Sooner
197
Recently I am reading a paper, and here the author gives the way of database representation.
I feel confused. Could someone give me an example of the so-called universe and histograms? My thought is that suppose a database has columns a b c, and |X| equals to 3. Each attribute is a type i. But how about ab ac bc abc? Will all counts of type i sum up to the size of database? Is $||x||_1$ the record number of the database(the size)? And how large is |X|?
definition computer-science
definition computer-science
asked Nov 27 at 2:42
Sooner
197
asked Nov 27 at 2:42
Sooner
197
asked Nov 27 at 2:42
Sooner
197
asked Nov 27 at 2:42
Sooner
197
asked Nov 27 at 2:42
Sooner
197
197
add a comment |
add a comment |
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