锅炉通风
Examine the data from the EMP table: The COMMISSION column shows the monthly commission earned by the employee.Which three tasks would require subqueries or joins in order to perform in a single step?（） Deleting the records of employees who do not earn commission.。 Increasing the commission of employee 3 by the average commission earned in department 20.。 Finding the number of employees who do NOT earn commission and are working for department 20.。 Inserting into the table a new employee 10 who works for department 20 and earns a commission that is equal to the commission earned by employee 3.。 Creating a table called COMMISSION that has the same structure and data as the columns EMP_ID and COMMISSIONS of the EMP table.。 Decreasing the commission by 150 for the employees who are working in department 30 and earning a commission of more then 800.。
下列类型中，不包括在消费者类型中的有（） 耐心购买者。 分析购买者。 冲动购买者。 兴趣购买者。
n个相同的电容器并联，其总电容为（）。 nc。 c。 c/。
You perform a backup using the following BACKUP command: RMAN> BACKUP AS COMPRESSED BACKUPSET DATABASE,Which statement is true of this command?（） A different procedure is required to restore a database from compressed backups 。 The AS COMPRESSED clause of the BACKUP command provided by RMAN is used to create compressed backup sets and image copies. 。 Using this command to create backups minimizes the bandwidth consumed.。 Using this command to create backups improves the performance of the backup process&e。
参加动火作业的焊工、电工、起重工等特种作业人员应（）
