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【单选题】
关于 SQL 视图更新的可执行性,下列说法不正确的是 _________ 。A.
如果视图是由单个表的列构成，但并没有包括主键，则不能更新
B.
如果视图中包括了 group by 子句，则不能更新
C.
对于由单一 Table 子集构成的视图，即如果视图是从单个基本表使用选择、投影操作导出的，并且包含了基本表的主键，则不能更新
D.
如果视图的 select 目标列包含聚集函数，则不能更新
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【单选题】用人单位自( )起即与劳动者建立劳动关系。已经建立劳动关系，未同时订立书面劳动合同的，应当自用工之日起( )内订立书面劳动合同。
A.
用工之日 1个月
B.
签订合同之日 3个月
C.
上级批准设立之日 2个月
D.
劳动者领取工资之日 15日
【简答题】已经建立劳动关系，未同时订立书面劳动合同的，应当自用工之日起多少天内订立书面劳动合同
【单选题】.Hardly_______when the fans began to scream with excitement.A．the star showed upB．did the star show
A.
Hardly_______when the fans began to scream with excitement. A.the star showed up
B.
did the star show up
C.
had the star showed up
D.
the star had showed up
【单选题】When the sports star showed up at the gate of the airport, some of his young female (女性) _________ got excited and started shouting.
A.
champion
B.
tennis
C.
court
D.
fans
【简答题】已经建立劳动关系，未同时订立书面劳动合同的，应当自用工之日起（）内订立书面劳动合同。
【单选题】When the star showed up on the stage, the ______ began to cheer( 欢呼).
A.
audience
B.
candidate
C.
baseball
【简答题】When the sports star showed up at the gate of the airport, some of his young female (女 ) ( ) got excited and started shouting.
【单选题】Once we learn the rules for map reading, they seem so simple: up is north, blue is water, a star stands for a capital. But when and how do we learn to read a map? Research shows that even three-year-o...
A.
children have better understanding than grown-ups
B.
children have special natural ability for map reading
C.
children are more interested in toys than in maps
D.
children can start to learn map-reading early
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