单选题What is true of using group functions on columns that contain NULL values?（）A Group functions on columns ignore NULL values.B Group functions on columns returning dates include NULL values.C Group functions on columns returning numbers include NULL val

题目
单选题
What is true of using group functions on columns that contain NULL values?（）
A

Group functions on columns ignore NULL values.

B

Group functions on columns returning dates include NULL values.

C

Group functions on columns returning numbers include NULL values.

D

Group functions on columns cannot be accurately used on columns that contain NULL values.

E

Group functions on columns include NULL values in calculations if you use the keyword INC_NULLS.

相似考题

1.What is true about updates through a view? ()A. You cannot update a view with group functions.B. When you update a view group functions are automatically computed.C. When you update a view only the constraints on the underlying table will be in effect.D. When you update a view the constraints on the views always override the constraints on the underlying tables.

2.The EMPLOYEES table has these columns:Management wants to add a default value to the SALARY column. You plan to alter the table by using this SQL statement:What is true about your ALTER statement?()A. Column definitions cannot be altered to add DEFAULT values.B. A change to the DEFAULT value affects only subsequent insertions to the table.C. Column definitions cannot be altered at add DEFAULT values for columns with a NUMBER data type.D. All the rows that have a NULL value for the SALARY column will be updated with the value 5000.

3.In which three cases would you use the USING clause?()A.You want to create a nonequijoin.B.The tables to be joined have multiple NULL columns.C.The tables to be joined have columns of the same name and different data types.D.The tables to be joined have columns with the same name and compatible data types.E.You want to use a NATURAL join, but you want to restrict the number of columns in the join condition.

4.In which scenario would index be most useful? ()A. The indexed column is declared as NOT NULL.B. The indexed columns are used in the FROM clause.C. The indexed columns are part of an expression.D. The indexed column contains a wide range of values.

更多“单选题What is true of using group functions on columns that contain NULL values?（）A Group functions on columns ignore NULL values.B Group functions on columns returning dates include NULL values.C Group functions on columns returning numbers include NULL val”相关问题

  • 第1题：

    Which statement is true regarding the INTERSECT operator?（）

    • A、It ignores NULL values 
    • B、Reversing the order of the intersected tables alters the result 
    • C、The names of columns in all SELECT statements must be identical 
    • D、The number of columns and data types must be identical for all SELECT statements in the query 

    正确答案:D

  • 第2题：

    What is true of using group functions on columns that contain NULL values?（）

    • A、Group functions on columns ignore NULL values.
    • B、Group functions on columns returning dates include NULL values.
    • C、Group functions on columns returning numbers include NULL values.
    • D、Group functions on columns cannot be accurately used on columns that contain NULL values.
    • E、Group functions on columns include NULL values in calculations if you use the keyword INC_NULLS.

    正确答案:A

  • 第3题：

    Which two are true about aggregate functions? （）

    • A、You can use aggregate functions in any clause of a SELECT statement.
    • B、You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
    • C、You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
    • D、You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
    • E、You can use aggregate functions on a table, only by grouping the whole table as one single group.
    • F、You cannot group the rows of a table by more than one column while using aggregate functions.

    正确答案:A,D

  • 第4题：

    Using the report wizard you create a tabular report to display all the columns in the EMP table. The records are ordered by the deptname and job columns. You need to create a hierarchical report that breaks on the deptname and job values. Using the data model how would you create this break structure?（）

    • A、Specify the break order on the gemp group Property palette. 
    • B、Specify a break order on the dept_name and job columns property palettes. 
    • C、Click and drag the dept_name and jobs column out and above of the gemp group to create a new parent group. 
    • D、Change the position of the dept_name and the job columns within the gemp group.

    正确答案:C

  • 第5题：

    The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds the highest grade point average (GPA) per semester?（）

    • A、SELECT MAX (gpa) FROM student _ grades WHERE gpa IS NOT NULL;
    • B、SELECT (gpa) FROM student _ grades GROUP BY semester_end WHERE gpa IS NOT NULL;
    • C、SELECT MAX (gpa) FROM student _ grades WHERE gpa IS NOT NULL GROUP BY semester_end;
    • D、SELECT MAX (gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student _ grades;
    • E、SELECT MAX (gpa) FROM student _ grades GROUP BY semester_end WHERE gpa IS NOT NULL;

    正确答案:C

  • 第6题：

    单选题
    In which scenario would index be most useful? （）
    A

    The indexed column is declared as NOT NULL.

    B

    The indexed columns are used in the FROM clause.

    C

    The indexed columns are part of an expression.

    D

    The indexed column contains a wide range of values.


    正确答案： D
    解析： 暂无解析

  • 第7题：

    单选题
    The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds the highest grade point average (GPA) per semester?（）
    A

    SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL;

    B

    SELECT (gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;

    C

    SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL GROUP BY semester_end;

    D

    SELECT MAX(gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student_grades;

    E

    SELECT MAX(gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;


    正确答案： B
    解析： 暂无解析

  • 第8题：

    多选题
    Which two statements are true about constraints? （）
    A

    The UNIQUE constraint does not permit a null value for the column.

    B

    A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.

    C

    The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.

    D

    The NOT NULL constraint ensures that null values are not permitted for the column.


    正确答案： A,B
    解析： 暂无解析

  • 第9题：

    单选题
    Which statement is true regarding the INTERSECT operator?（）
    A

    It ignores NULL values 

    B

    Reversing the order of the intersected tables alters the result 

    C

    The names of columns in all SELECT statements must be identical 

    D

    The number of columns and data types must be identical for all SELECT statements in the query 


    正确答案： D
    解析： 暂无解析

  • 第10题：

    单选题
    What is true of using group functions on columns that contain NULL values?（）
    A

    Group functions on columns ignore NULL values.

    B

    Group functions on columns returning dates include NULL values.

    C

    Group functions on columns returning numbers include NULL values.

    D

    Group functions on columns cannot be accurately used on columns that contain NULL values.

    E

    Group functions on columns include NULL values in calculations if you use the keyword INC_NULLS.


    正确答案： D
    解析： 暂无解析

  • 第11题：

    Which two statements are true regarding views?（）

    • A、A subquery that defines a view cannot include the GROUP BY clause 
    • B、A view that is created with the subquery having the DISTINCT keyword can be updated 
    • C、A view that is created with the subquery having the pseudo column ROWNUM keyword cannot be updated 
    • D、A data manipulation language (DML) operation can be performed on a view that is created with the subquery having all the NOT NULL columns of a table

    正确答案:C,D

  • 第12题：

    Which two statements are true about constraints? （）

    • A、The UNIQUE constraint does not permit a null value for the column.
    • B、A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.
    • C、The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.
    • D、The NOT NULL constraint ensures that null values are not permitted for the column.

    正确答案:B,D

  • 第13题：

    What is true about updates through a view? （）

    • A、You cannot update a view with group functions.
    • B、When you update a view group functions are automatically computed.
    • C、When you update a view only the constraints on the underlying table will be in effect.
    • D、When you update a view the constraints on the views always override the constraints on the underlying tables.

    正确答案:A

  • 第14题：

    The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds the highest grade point average (GPA) per semester?（）

    • A、SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL;
    • B、SELECT (gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;
    • C、SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL GROUP BY semester_end;
    • D、SELECT MAX(gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student_grades;
    • E、SELECT MAX(gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;

    正确答案:C

  • 第15题：

    In which scenario would index be most useful?（）

    • A、The indexed column is declared as NOT NULL.
    • B、The indexed columns are used in the FROM clause.
    • C、The indexed columns are part of an expression.
    • D、The indexed column contains a wide range of values.

    正确答案:D

  • 第16题：

    单选题
    Using the report wizard you create a tabular report to display all the columns in the EMP table. The records are ordered by the deptname and job columns. You need to create a hierarchical report that breaks on the deptname and job values. Using the data model how would you create this break structure?（）
    A

    Specify the break order on the gemp group Property palette. 

    B

    Specify a break order on the dept_name and job columns property palettes. 

    C

    Click and drag the dept_name and jobs column out and above of the gemp group to create a new parent group. 

    D

    Change the position of the dept_name and the job columns within the gemp group.


    正确答案： B
    解析： 暂无解析

  • 第17题：

    单选题
    The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds the highest grade point average (GPA) per semester?（）
    A

    SELECT MAX (gpa) FROM student _ grades WHERE gpa IS NOT NULL;

    B

    SELECT (gpa) FROM student _ grades GROUP BY semester_end WHERE gpa IS NOT NULL;

    C

    SELECT MAX (gpa) FROM student _ grades WHERE gpa IS NOT NULL GROUP BY semester_end;

    D

    SELECT MAX (gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student _ grades;

    E

    SELECT MAX (gpa) FROM student _ grades GROUP BY semester_end WHERE gpa IS NOT NULL;


    正确答案： C
    解析： 暂无解析

  • 第18题：

    单选题
    What is true about updates through a view?（）
    A

    You cannot update a view with group functions.

    B

    When you update a view group functions are automatically computed.

    C

    When you update a view only the constraints on the underlying table will be in effect.

    D

    When you update a view the constraints on the views always override the constraints on the underlying tables.


    正确答案： B
    解析： 暂无解析

  • 第19题：

    多选题
    Which two statements are true regarding views?（）
    A

    A subquery that defines a view cannot include the GROUP BY clause

    B

    A view that is created with the subquery having the DISTINCT keyword can be updated

    C

    A view that is created with the subquery having the pseudo column ROWNUM keyword cannot be updated

    D

    A data manipulation language (DML) operation can be performed on a view that is created with the subquery having all the NOT NULL columns of a table


    正确答案： D,B
    解析： 暂无解析

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