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单项选择题
A. The main query executes with the first value returned by the subquery.
B. The main query executes with the last value returned by the subquery.
C. The main query executes with all the values returned by the subquery.
D. The main query fails because the multiple-row subquery cannot be used with the comparison operator.
E. You cannot define a multiple-row subquery in the WHERE clause of a SQL query.
多项选择题
A. Constraints provide data independence.
B. Constraints make complex queries easy.
C. Constraints enforce rules at the view level.
D. Constraints enforce rules at the table level.
E. Constraints prevent the deletion of a table if there are dependencies.
F. Constraints prevent the deletion of an index if there are dependencies.
多项选择题
A. TRIM
B. REPLACE
C. TRUNC
D. TO_DATE
E. MOD
F. CASE
单项选择题
A. Selection, projection, join
B. Difference, projection, join
C. Selection, intersection, join
D. Intersection, projection, join
E. Difference, projection, product
单项选择题
A. Use the DESCRIBE command in the EMP_DEPT VU view.
B. Use the DEFINE VIEW command on the EMP_DEPT VU view.
C. Use the DESCRIBE VIEW command on the EMP_DEPT VU view.
D. Query the USER_VIEWS data dictionary view to search for the EMP_DEPT_VU view.
E. Query the USER_SOURCE data dictionary view to search for the EMP_DEPT_VU view.
F. Query the USER_OBJECTS data dictionary view to search for the EMP_DEPT_VU view.
单项选择题
A. SELECT last_name FROM EMP WHERE last_ name LIKE '_A%';
B. SELECT last_name FROM EMP WHERE last name ='*A%'
C. SELECT last_name FROM EMP WHERE last name ='_A%';
D. SELECT last_name FROM EMP WHERE last name LIKE '*A%'
单项选择题
A. =
B. LIKE
C. BETWEEN
D. NOT IN
E. IS
F. <>
单项选择题
A. CREATE INDEX NAME _IDX (first_name, last_name);
B. CREATE INDEX NAME _IDX (first_name, AND last_name)
C. CREATE INDEX NAME_IDX ON (First_name, last_name);
D. CREATE INDEX NAME_IDX ON employees (First_name, AND last_name);
E. CREATE INDEX NAME_IDX ON employees (First_name, last_name);
F. CREATE INDEX NAME_IDX FOR employees (First_name, last_name);
多项选择题
A. Must begin with either a number or a letter.
B. Must be 1-30 characters long.
C. Should not be an Oracle Server reserved word.
D. Must contain only A-Z, a-z, 0-+, _, *, and #.
E. Must contain only A-Z, a-z, 0-9, _, $, and #.
F. Must begin with a letter.
多项选择题
A. You use a NEXTVAL pseudo column to look at the next possible value that would be generated from a sequence, without actually retrieving the value.
B. You use a CURRVAL pseudo column to look at the current value just generated from a sequence, without affecting the further values to be generated from the sequence.
C. You use a NEXTVAL pseudo column to obtain the next possible value from a sequence by actually retrieving the value from the sequence.
D. You use a CURRVAL pseudo column to generate a value from a sequence that would be used for a specified database column.
E. If a sequence starting from a value 100 and incremented by 1 is used by more then one application, then all of these applications could have a value of 105 assigned to their column whose value is being generated by the sequence.
F. You use REUSE clause when creating a sequence to restart the sequence once it generates the maximum value defined for the sequence.