问题
单项选择题
在SQL语言的SELECT语句中，实现投影操作的是哪个子句
A．SELECT
B．FROM
C．WHERE
D．GROUP BY
答案
参考答案：A
解析： 在SQL语言的SELECT语句中，实现投影操作的是SELECT。
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在SQL语言的SELECT语句中，实现投影操作的是哪个子句
A．SELECT
B．FROM
C．WHERE
D．GROUP BY
参考答案：A
解析： 在SQL语言的SELECT语句中，实现投影操作的是SELECT。
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| It was winter, and Mrs Black wanted to do some shopping. So she waited 1 it was Saturday. When her husband 2 , she took him to the shops with her to pay for everything and ot carry her bags. They went to a lot of shops, and Mrs Black 3 a lot of things. She often 4 and said,"look, Joe! Isn't that beautiful?" He then answered," All right, dear. How 5 is it?" And took his money 6 to pay for it. It was dark when they came out of the last 7 , and Mr Black was very 8 and thinking about other things, like a nice drink at home. Suddenly his wife looked up at the sky and said,"Look 9 the beautiful moon, Joe!" Without stopping, Mr Black answered, "All right. How 10 is it?" | ||||
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