单选题 In which scenario would index be most useful?()
The indexed column is declared as NOT NULL.
The indexed columns are used in the FROM clause.
The indexed columns are part of an expression.
The indexed column contains a wide range of values.
多选题 Which two are character manipulation functions? ()
TRIM
REPLACE
TRUNC
TO_DATE
MOD
CASE
单选题 You need to calculate the total of all salaries in the accounting department. Which group function should you use? ()
MAX
MIN
SUM
COUNT
TOTAL
LARGEST
单选题 The EMPLOYEES table contains these columns: EMPLOYEE_ID NUMBER(4) LAST_NAME VARCHAR2 (25) JOB_ID VARCHAR2(10) You want to search for strings that contain 'SA_' in the JOB_ID column. Which SQL statement do you use?()
SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA/_%' ESCAPE '/';
SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_';
SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_' ESCAPE /;
SELECT employee_id, last_name, job_id FROM employees WHERE job_id = '%SA_';
单选题 Which SELECT statement should you use to extract the year from the system date and display it in the format "1998"?()
SELECT TO_CHAR(SYSDATE,'yyyy') FROM dual;
SELECT TO_DATE(SYSDATE,'yyyy') FROM dual;
SELECT DECODE(SUBSTR(SYSDATE, 8), 'YYYY') FROM dual;
SELECT DECODE(SUBSTR(SYSDATE, 8), 'year') FROM dual;
SELECT TO_CHAR(SUBSTR(SYSDATE, 8,2),'yyyy') FROM dual;
单选题 You need to perform these tasks: 1. Create and assign a MANAGER role to Blake and Clark 2. Grant CREATE TABLE and CREATE VIEW privileges to Blake and Clark Which set of SQL statements achieves the desired results?()
CREATE ROLE manager; GRANT create table, create view TO manager; GRANT manager TO BLACK, CLARK;
CREATE ROLE manager; GRANT create table, create voew TO manager; GRANT manager ROLE TO BLACK, CLARK;
GRANT manager ROLE TO BLACK, CLARK; GRANT create table, create voew TO BLACK CLARK; ***MISSING***
多选题 What are two reasons to create synonyms?()
You have too many tables.
Your tables are too long.
Your tables have difficult names.
You want to work on your own tables.
You want to use another schema's tables.
You have too many columns in your tables.
单选题 Evaluate the set of SQL statements: CREATE TABLE dept (deptno NUMBER(2), dname VARCNAR2(14), 1oc VARCNAR2 (13)); ROLLBACK; DESCRIBE DEPT What is true about the set?()
The DESCRIBE DEPT statement displays the structure of the DEPT table.
The ROLLBACK statement frees the storage space occupies by the DEPT table.
The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.
The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.
单选题 You need to change the definition of an existing table. The COMMERCIALS table needs its DESCRIPTION column changed to hold varying length characters up to 1000 bytes. The column can currently hold 500 bytes per value. The table contains 20000 rows. Which statement is valid?()
ALTER TABLE commercials MODIFY (description CHAR2(1000));
ALTER TABLE commercials CHANGE (description CHAR2(1000));
ALTER TABLE commercials CHANGE (description VARCHAR2(1000));
ALTER TABLE commercials MODIFY (description VARCHAR2(1000));
You cannot increase the size of a column if the table has rows.
单选题 Click the Exhibit button to examine the structures of the EMPLOYEES, DEPARTMENTS, and TAX tables. For which situation would you use a nonequijoin query?()
to find the tax percentage for each of the employees
to list the name, job_id, and manager name for all the employees
to find the name, salary, and the department name of employees who are not working with Smith
to find the number of employees working for the Administrative department and earning less than 4000
to display name, salary, manager ID, and department name of all the employees, even if the employees do not have a department ID assigned
在任何情况下,伸缩调节器处轨距的要求为()。
人类有两套影响学习的记忆系统:陈述性记忆和程序记忆。陈述性记忆是对事实或者词汇之类基本认识的记忆。而程序记忆,就是一个人“不劳而获”的记忆。程序记忆是人养成习惯和习得技巧的方式,比如骑自行车。在很多时候,这种学习是无意识的。人们用早期发育的程序记忆系统来学习复杂的东西,比如语法规则。帮助人们学习词汇的陈述性记忆系统,则需要更多时问完成发育。儿童拥有程序记忆系统,并且不受陈述性记忆系统的干扰。由此可以推出()。
宋末元初四大家
公平目标的实现可以通过()实现。
荟萃分析
人员安全疏散分析的性能判定标准为:可用疏散时间(A.SET)必须()必需疏散时间(RSET)。
预防HIV感染的主要措施应当为( )
简述我国混合型债券市场的发展状况。
造成水中某些污染物在生物体内含量大大高于水体中的浓度的生物放大作用是指()
输血的适应证中,不包括()