单项选择题
A database exists as a read-intensive server that is operating with query_cachek_type =DEMAND.
The database is refreshed periodically, but the resultset size of the queries does not fluctuate.
Note the following details about this environment: A web application uses a limited set of queries. The Query Cache hit rate is high.
All resultsets fit into the Query Cache. All queries are configured to use the Query Cache successfully. The response times for queries have recently started to increase.
The cause for this has correctly been identified as the increase in the number of concurrent users accessing the web service.
Based solely on the information provided, what is the most likely cause for this slowdown at the database level?（）
A.The Query Cache is pruning queries due to an increased number of requests
B.Query_cache_min_res_unit has been exceeded, leading to an increased performance overhead due to additional memory block lookups
C.Mutex contention on the Query Cache is forcing the queries to take longer due to its singlethreaded nature
D.The average resultset of a query is increasing due to an increase in the number of users requiring SQL statement execution
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多项选择题
Mysqldump was used to create a single schema backup; Shell> mysqldump –u root –p sakila > sakila2013.sql Which two commands will restore the sakila database without interfering with other running database?（）
A.Mysql＞ USE sakila; LOAD DATA INFILE 'sakila2013.sql';
B.Shell＞ mysql –u root –p sakila sakila2013.sql
C.Shell＞ mysql import –u root –p sakila sakila2013.sql
D.Shell＞ mysql –u root -p –e 'use sakila; source sakila2013.sql'
E.Shell＞ mysql –u root –p –silent ＜ sakila2013.sql -
单项选择题
ROW-based replication has stopped working. You investigate the error log file and find the following entries: 2013-08-27 14:15:47 9056 [ERROR] Slave SQL: Could not execute Delete_rows event on table test.t1; Cant find record in t1, Error_code: 1032; handler error HA_ERR_KEY_NOT_FOUND; the events master log 56_master-bin. 000003, end_log_pos 851, Error_code: 1032 2013-08-27 14:15:47 9056 [warning] Slave: Cant find record in t1 Error_code: 1032 2013-08-27 14:15:47 9056 [ERROR] Error running query, slave SQL thread aborted. Fix the problem, and restart the slave SQL thread with "SLAVE START". We stopped at log 56_masterbin. 000003 position 684 Why did you receive this error?（）
A.The slave SQL thread does not have DELETE privileges to execute on test.t1 table.s
B.The table definition on the slave -litters from the master
C.Multi-threaded replication slaves can have temporary errors occurring for cross database updates
D.The slave SQL thread attempted to remove a row from the test.t1 table, but the row did not exist -
单项选择题
Consider the following statement on a RANGE partitioned table: ALTER TABLE orders DROP PARTITION p1, p3; What is the outcome of executing the above statement?（）
A.A syntax error will result as you cannot specify more than one partition in the same statement
B.All data in p1 and p3 partitions are removed and the table definition is changed
C.All data in p1 and p3 partitions are removed, but the table definition remains unchanged
D.Only the first partition (p1) will be dropped as only one can be dropped at any time
