查询学生关系中所有学生姓名的操作属于关系运算中的( )。
A、投影
B、选择
C、连接
D、查找
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In your production database, data manipulation language (DML) operations are executed on the SALES table.You have noticed some dubious values in the SALES table during the last few days. You are able to track users, actions taken, and the time of the action for this particular period but the changes in data are not tracked.You decide to keep track of both the old data and new data in the table along with the user information. Whataction would you take to achieve this task()
A、Apply fine-grained auditing.
B、Implement value-based auditing.
C、Impose standard database auditing to audit object privileges.
D、Impose standard database auditing to audit SQL statements.
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以下类型的网络中,数据在网上传输速度最快的是()
A、Internet
B、LAN
C、MAN
D、WAN
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Red Hat Enterprise Linux版本分为()。
ARed Hat Enterprise LinuxAS
BRed Hat Enterprise LinuxES
CRed Hat Enterprise LinuxBS
DRed Hat Enterprise LinuxWS
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对利润表的2008年前三季度数据进行定基分析,其第三季度数据结果是()。
A、第三季度数据与第一季度数据的差
B、第三季度数据与第一季度数据的比
C、第三季度数据与第二季度数据的差
D、第三季度数据与第二季度数据的比
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What recommendations does the SQL Access Advisor provide for optimizing SQL queries?()
Aselection of SQL plan baselines
Bpartitioning of tables and indexes
Ccreation of index-organized tables
Dcreation of bitmap, function-based, and B-tree indexes
Eoptimization of materialized views for maximum query usage and fast refresh