KillTest 质量更高服务更好学习资料半年免费更新服务

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2 Exam : Title : Certified MySQL 5.0 DBA Part I Version : Demo 1 / 10

3 1. Will the following SELECT query list all of the tables in the INFORMATION_SCHEMA database? If not, why? SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'INFORMATION_SCHEMA' ORDER BY TABLE_NAME A. Yes. B. No; the INFORMATION_SCHEMA database does not contain information on itself. C. No; the WHERE clause is incorrect. The correct field name is TABLE_SCHEMATA. D. No; there is no table in the INFORMATION_SCHEMA database called TABLES. Answer: A 2. Which of the following are some general capabilites of the mysql client program? A. Create and Drop databases B. Ping the server C. Create, Drop, and modify tables and indexes. D. Shutdown the server. E. Create users. F. Display replication server status. Answer: ACEF 3. Suppose you have a server that has been started with the --myisam-recover option. When does the server perform the check on the MyISAM tables? A. Each time the server is started. B. Each time it encounters an error. C. Each time it opens the MyISAM table files. D. Each time the CHECK TABLE command is issued. Answer: C 4. Consider the following query: DELETE FROM INFORMATION_SCHEMA.TABLES 2 / 10

4 WHERE table_schema = 'world' AND table_name = 'Country' What would be the result of executing this query? A. An error would be issued B. A warning would be issued C. The row would be deleted from the INFORMATION_SCHEMA.TABLES table, and the table Country would be dropped from the world database D. The row would be deleted from the INFORMATION_SCHEMA, but the table Country in the world database would be unaffected. Answer: A 5. Which mysqld command line option disables incoming TCP/IP connections? A. --shared-memory B. --memlock C. --no-networking D. --skip-networking Answer: D 6. What are some advantages of using the SHOW command rather than using the INFORMATION_SCHEMA? A. It is available for releases older than MySQL 5.0. B. It returns results quicker than using the INFORMATION_SCHEMA. C. Using SHOW can provide more concise information. D. SHOW is a feature of standard SQL, and INFORMATION_SCHEMA is a MySQL specific command. Answer: AC 7. Index analysis and optimization using ANALYZE and OPTIMIZE statements should... A. generally never be run manually B. be run once the table reaches 100,000 rows or above C. be run when more than 5% of the rows are changed by a single statement 3 / 10

5 D. be run when EXPLAIN SELECT shows that an inordinate amount of rows is expected to be read during query execution E. be run when you suspect that a table is heavily fragmented Answer: DE 8. Suppose you have a column in which most records are going to be between 30 and 32 characters. Which of the following column types would be most efficient? A. VARCHAR B. CHAR C. TEXT D. Either VARCHAR or CHAR Answer: B 9. Which of the following APIs/connectors are included in a MySQL distribution? A. Connector/J B. Connector/ODBC C. C API D. Connector/NET E. Connector/MJX Answer: C 10. Which of the following are some benefits of using MySQL built binaries over binaries built by yourself? A. They are highly optimized. B. They are cross-platform. C. Many are built using commercial compilers that produce a better quality build than with freely available compilers. D. They will work with tools such as MySQL Administrator and MySQL Query Browser. E. They may include libraries not available in the standard operating system library. Answer: ACE 4 / 10

6 11. Assume you compile MySQL from source and invoke configure with the following options. --with-charset=latin1 --with-extra-charsets=utf8,ucs2 Compared to a standard binary installation that contains many more character sets, which of the following statements is/are true? A. The compiled version will use less disk space, because only a few character sets will be installed on disk. B. The compiled version will use less memory, because only a few character sets will be loaded by the server. C. The compiled version will use less file handles, because only a few files need to be opened when the server is started. Answer: AB 12. Which of the following are true for how BTREE and HASH index types should be used for MEMORY tables? A. HASH index types are only for use with equality comparisions such as those using the = and <=> operators. B. BTREE index types are preferable for use with comparisons that do not just use equality operators such as = and <=> C. BTREE index types are only for use with equality comparisons such as those using the = and <=> operators. D. HASH index types are preferable for use with comparisons that do not just use equality operators such as = and <=> Answer: AB 13. Which of the following are some general properties of the mysqlimport client program? A. It loads data files into tables. B. It can load files only on the server host. C. It provides a command-line interface to the LOAD DATA INFILE. D. It can load files both on the client and server host. E. It bypasses the server and writes directly to the corresponding data files. 5 / 10

7 Answer: ACD 14. Which of the following statements are true? A. InnoDB supports Foreign Keys. B. MyISAM supports Foreign Keys. C. InnoDB supports cascaded DELETE statements. D. MyISAM supports cascaded DELETE statements. E. InnoDB supports cascaded UPDATE statements. F. MyISAM supports cascaded UPDATE statements. Answer: ACE 15. In a standard MySQL installation which of following files are stored below the data directory? A. Format files for all the tables B. Data and index files for MyISAM tables C. InnoDB tablespace files D. General server logs E. MySQL upgrade script files Answer: ABCD 16. Which of the following statements is true for mysqldump? A. It can dump data only on remote servers. B. It can dump data only on the local server. C. It can dump data on both local and remote servers. Answer: C 17. Which of the following best describes the scope of explicitly and implicitly set locks? A. Explicitly set locks may span several commands. B. Implicitly set locks may span several commands. C. Implicitly set locks will span only one statement or transaction. D. Explicitly set locks will span only one statement or transaction. 6 / 10

8 Answer: ABC 18. MySQL is a multi-threaded database server. Every connection to the database server is handled by it's own thread. A. True B. False Answer: A 19. Which of the following are true regarding the table cache? A. It is used to cache row data in open tables B. It holds file descriptors for open tables C. The size of the table cache may be set per-session D. Each connection has its own table cache. They are of equal size, set globally. E. There is one table cache, shared among all sessions. F. Increasing the size of the variable table_cache allows mysqld to keep more tables open simultaneously Answer: BEF 20. The ANALYZE TABLE command should be used... A. When you need to find out why a query is taking a long time to execute. B. To improve performance by updating index distribution statistics. C. After large amounts of table data have changed. D. To check a tables structure to see if it may have been damaged and needs repair. Answer: BC 21. Which of the following statements are true regarding the InnoDB storage engine? A. It uses multiversioning to isolate transactions. B. It is not possible for deadlocks to occur. C. It does not isolate transactions. D. It is possible for deadlocks to occur. Answer: AD 7 / 10

9 22. What are some properties of using LOCK TABLE? A. Less work is required by the server to acquire and release locks. B. It can only be used with the MyISAM storage engine. C. Using LOCK TABLE sometimes decreases the amount disk reads and writes needed for a group of statements. D. All tables must be locked in a single statement. E. It creates more disk activity. Answer: ACD 23. mysqldump can be instructed to include commands to drop and recreate tables before trying to create or load data. A. True B. False Answer: A 24. Which of the following are requirements for MyISAM binary portability? A. Both machines must use the same operating system. B. Database and table names must use lowercase format. C. Both machines must use IEEE floating-point format or contain no floating-point columns. D. Both machines must use two's-complement integer arithmetic. Answer: CD 25. Another user has issued the statement LOCK TABLE pets FOR WRITE You can... A. Update table pets B. SELECT from table pets C. Update and SELECT from table pets D. None of the above Answer: D 8 / 10

10 26. Which of the following actions are performed during an RPM installation of the MySQL server package? A. Setup a mysql user B. Setup a mysql group C. Initialize the data directory D. Setup passwords for all default accounts. Answer: ABC 27. Which of the following steps should be taken to restore an InnoDB table to a consistent state without having to shutdown the server? A. Run the REPAIR TABLE command. B. Dump the table with mysqldump, drop the table then re-create from the dump file. C. Run the CHECK TABLE command. D. Dump the table with mysqlhotcopy, drop the table then re-create with the backup file. Answer: B 28. Which of the following best describes why table locking is often not desirable compared to page or row locking? A. Table locks can have deadlocks. B. Table locks create concurrency issues. C. Table locks prevent other clients from making any changes to the table until released. D. Table locks can cause data corruption issues if more than one client tries to make changes while locked. Answer: BC 29. Which of the following statements are true regarding table locks? A. They can only be released by the client holding them. B. They can be released by other connections than the client holding them. C. They are implicitly released when the connection is closed. 9 / 10

11 D. They are not released when the connection is closed Answer: AC 30. Which of the following correctly defines dirty reads, non-repeatable reads and phantom row? A. A dirty read is a read by one transaction of uncommitted changes made by another transaction. B. A dirty read is a read by one transaction of its uncommitted changes. C. A non-repeatable read occurs when a transaction performs the same retreival twice but gets a different result each time. D. A non-repeatable read is a row that appears where it was not visible before. E. A phantom is a row that appears where it was not visible before. F. A phantom is a read by one transaction of uncommitted changes made by another transaction. Answer: ACE 10 / 10

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KillTest 质量更高 服务更好 学习资料 半年免费更新服务

KillTest 质量更高服务更好学习资料半年免费更新服务