Which of the following is not a predefined symbolic constant?

Some database systems require the columns in a column expression to be referenced in the GROUP BY clause in which manner?

a. The column expression is referenced by the correlation name. b. The columns are referenced in the exact same manner they are referenced in the column expression. c. The column expression is referenced by its relative column number starting with 1 for the first column.

What minimal operating system has only the services needed to access the network, work with files, copy disk images, and jump-start a Windows installation?

A. Windows Image File B. Windows Preinstallation Environment C. Windows Preboot Environment D. Windows Network Boot