which scenario would an index be most useful?

In which scenario would an index be most useful? A.The indexed columns are part of an expression. B.The indexed column is declared as NOT NULL. C.The indexed column contains a wide range of values. D.The indexed columns are used in the FROM clause. Explanation: Index will be useful if the indexed column contains a wide […]

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Which are DML statements?

Which are DML statements? (Choose all that apply.) A.DROP… B.COMMIT C.DELETE D.MERGE E.UPDATE F.CREATE Explanation: MERGE, UPDATE and DELETE commands are data manipulation language (DML) statements. Show Answer

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Which two are attributes of iSQL*Plus?

Which two are attributes of iSQL*Plus? (Choose two.) A./SQL*Plus commands cannot be abbreviated. B./SQL*Plus commands are accessed from a browser. C./SQL*Plus commands are used to manipulate data in tables. D./SQL*Plus commands manipulate table definitions in the database. E./SQL*Plus is the Oracle proprietary interface for executing SQL statements. Explanation: D: SQL*Plus commands can be used to […]

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Which values are displayed?

Evaluate the SQL statement:SELECT ROUND(45.953, -1), TRUNC(45.936, 2)FROM dual;Which values are displayed? A.45.95 and 45.93 B.50 and 45.93 C.46 and 45 D.50 and 45.9 E.46 and 45.93 F.45 and 45.93 Explanation: :ROUND (45.953,-1) will round value to 1 decimal places to the left.TRUNC (45.936,2) will truncate value to 2 decimalThe answer will be 50 and […]

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Which SQL statement returns a numeric value?

Which SQL statement returns a numeric value? A.SELECT ADD_MONTHS(MAX(hire_Date), 6) FROM EMP; B.SELECT sysdate-hire_date FROM EMP; C.SELECT TO_NUMBER(hire_date + 7) FROM EMP; D.SELECT ROUND(hire_date) FROM EMP; Explanation: : DATE value subtract DATE value will return numeric value.Refer : Introduction to Oracle9i : SQL, Oracle University Study Guide, 9-13 Show Answer

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Which two are true about aggregate functions?

Which two are true about aggregate functions? (Choose two.) A.You can use aggregate functions in any clause of a SELECT statement. B.You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns. C.You can use aggregate functions only in the column list […]

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Which SQL statement produces an error?

Examine the structure of the EMP_DEPT_VU view:Column Name Type RemarksEMPLOYEE_ID NUMBER From the EMPLOYEES tableEMP_NAME VARCHAR2(30) From the EMPLOYEES tableJOB_ID VARCHAR2(20) From the EMPLOYEES tableSALARY NUMBER From the EMPLOYEES tableDEPARTMENT_ID NUMBER From the DEPARTMENTS tableDEPT_NAME VARCHAR2(30) From the DEPARTMENTS tableWhich SQL statement produces an error? A.None of the statements produce an error; all are valid. […]

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Which statement accomplishes this task?

You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. Thetable is currently empty. Which statement accomplishes this task? A.ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id; B.ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id); C.ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id); D.ALTER TABLE students ADD […]

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