James Blair
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College Stats 224 Quiz am Quiz 3, erstellt von James Blair am 12/03/2015.

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James Blair
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Quiz 3

Frage 1 von 10

1

Which of the following statements regarding the ALTER TABLE statement is false?

Wähle eine der folgenden:

  • a. It allows you to update column attributes.

  • b. It allows you to drop columns in your table.

  • c. It allows you to change a character column to a numeric column.

  • d. It allows you to add new columns in your table.

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Frage 2 von 10

1

Which of the following is not a type of integrity constraint?

Wähle eine der folgenden:

  • a. NULL

  • b. UNIQUE

  • c. PRIMARY KEY

  • d. CHECK

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Frage 3 von 10

1

Which of the following PROC SQL steps gives bonuses (in points) to frequent-flyer program members as follows:
a 50% bonus for members who traveled less than 10,000 miles
a 100% bonus for members who traveled 10,000 miles or more?

Wähle eine der folgenden:

  • a. proc sql;
    update work.frequentflyers
    set pointsearned=pointsearned*
    case when milestraveled < 10000
    then pointsearned*1.5
    when milestraveled >= 10000
    then pointsearned*2
    else pointsearned*1
    end;

  • b. proc sql;
    update work.frequentflyers
    set pointsearned=pointsearned*
    case if milestraveled < 10000
    then pointsearned*1.5
    if milestraveled >= 10000
    then pointsearned*2
    else pointsearned*1
    end;

  • c. proc sql;
    update work.frequentflyers
    set pointsearned=pointsearned*
    case when milestraveled < 10000
    then 1.5
    when milestraveled >= 10000
    then 2
    else 1

    end;

  • d. proc sql;
    update work.frequentflyers
    set pointsearned=pointsearned*
    case if milestraveled < 10000
    then 1.5
    if milestraveled >= 10000 then 2
    else 1

    end;

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Frage 4 von 10

1

Which of the following creates an empty table that contains the 2 columns FullName and Age?

Wähle eine der folgenden:

  • a. proc sql;
    create work.names
    (FullName char(25), Age num);

  • b. proc sql;
    create table work.names
    set (FullName char(25), Age num);

  • c. proc sql;
    create table work.names
    (FullName char(25), Age num);

  • d. proc sql;
    create table work.names as
    (FullName char(25), Age num);

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Frage 5 von 10

1

Which statement is false regarding the keyword CORRESPONDING?

Wähle eine der folgenden:

  • a. It cannot be used with the keyword ALL.

  • b. When used in EXCEPT, INTERSECT, and UNION set operations, it removes any columns not found in both tables.

  • c. It overlays columns by name, not by position.

  • d. When used in OUTER UNION set operations, it causes same-named columns to be overlaid.

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Frage 6 von 10

1

Using an index is not likely to optimize a PROC SQL query in which of the following situations?

Wähle eine der folgenden:

  • a. The query contains an IN subquery that references the key column.

  • b. The query is an equijoin, and all the columns in the join expression are indexed in one of the tables being joined.

  • c. The key column is specified only in a SELECT clause.

  • d. The key column is specified in a WHERE clause expression that contains a comparison operator, the TRIM or SUBSTR function, the CONTAINS operator, or the LIKE operator.

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Frage 7 von 10

1

Which of the following will create a composite index for the table Sasuser.Flightdelays? (Sasuser.Flightdelays contains the following columns: Date, FlightNumber, Origin, Destination, DelayCategory, DestinationType, DayOfWeek, and Delay.)

Wähle eine der folgenden:

  • a. proc sql;
    create composite index places
    on sasuser.flightdelays (flightnumber, destination);

  • b. proc sql;
    create index on flightnumber,destination
    from sasuser.flightdelays (places);

  • c. proc sql;
    create index destination
    on sasuser.flightdelays(flightnumber, destination);

  • d. proc sql;
    create index places
    on sasuser.flightdelays (flightnumber, destination);

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Frage 8 von 10

1

Which keyword must you add to your index definition in the CREATE INDEX
statement to ensure that no duplicate values of the key column can exist?

Wähle eine der folgenden:

  • a. KEY

  • b. UNIQUE

  • c. NODUPKEY

  • d. NODUPS

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Frage 9 von 10

1

Which of the following is false regarding the IDXNAME= data set option?

Wähle eine der folgenden:

  • a. The option allows you to create and name an index on the table.

  • b. The option directs SAS to use an index that you specify.

  • c. The specified index must be suitable by having at least its first or only column match a condition in the WHERE expression.

  • d. The specified index must exist.

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Frage 10 von 10

1

In order for PROC SQL to perform an inner join,

Wähle eine der folgenden:

  • a. the columns that are specified in a join condition in the WHERE clause must have the same data type.

  • b. the columns that are specified in a join condition in the WHERE clause must have the same name.

  • c. the tables being joined must contain the same number of columns.

  • d. the tables must be sorted before they are joined.

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