ADO.NET中，要向DataTable对象中添加一列，以下C#代码正确的是（选一项） A: myTable = new DataTable("Months"); myTable.Columns.Add("Month", string); B: myTable = new DataTable("Months"); myTable.Columns.Add("Month", typeof(string)); C: myTable = new DataTable("Months"); myTable.Columns.Add("string",Month)); D: myTable = new DataTable("Months"); myTable.Columns.Add(string ,"Month"));

在SQLServer中，下列标识符可以作为本地临时表名的是（）。 A: ##MyTable B: @@MyTable C: @MyTable D: #MyTable

完成轴网与柱子绘制后再绘制梁。Add grids and columns before adding beams.

写出删除MyTable表的SQL语句。

Hive中的这条命令“ALTER TABLE employed ADD columns（column string）”是什么含义？ A: 修改文件格式 B: 删除表 C: 创建表 D: 添加列

What are the features of columns?（ ） A: Columns are usually characterized by fixed names and locations. B: Columns are printed pages where manuscripts of certain contents are published. C: Columns are relatively independent in the overall layout of newspapers and periodicals. D: Articles in columns are of various styles.

要删除mytable表中的myindex索引，可以使用（）语句。

If a is known to be a 2×3 matrix, then after executing a=a(:), ( ). A: a transforms to a column vector B: a transforms to 3 rows and 2 columns C: a transforms to 3 rows and 3 columns D: a transforms to 2 rows 3 and columns

Which of the following are the types of columns encountered in gas chromatography?(1) flat plates (2) packed columns (3) plastic strips (4) open tubular, or capillary columns A: 1,2 B: 3, 4 C: 1, 3 D: 2,4

The Greek orders of columns are used including