7.3. Select Lists
7.3.选择列表
As shown in the previous section, the table expression in the
SELECT
command constructs an intermediate
virtual table by possibly combining tables, views, eliminating rows, grouping, etc. This table
is finally passed on to processing by the
select list
. The select list determines which
columns
of the
intermediate table are actually output.
正如前几节所示，
SELECT命令中的表表达式通过组合表，视图，筛选行，分组等来构造中间虚拟表。该表最终由选择列表传递并进行处理。选择列表确定实际输出中间表的哪些列。
