SQL小测试

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1.SQL 指的是?\

Structured Query Language

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2.哪个 SQL 语句用于从数据库中提取数据?\

SELECT

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3.哪条 SQL 语句用于更新数据库中的数据?\

UPDATE

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4.哪条 SQL 语句用于删除数据库中的数据?\

DELETE

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5.哪条 SQL 语句用于在数据库中插入新的数据?\

INSERT INTO

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6.通过 SQL,您如何从 "Persons" 表中选取 "FirstName" 列?\

SELECT FirstName FROM Persons

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7.通过 SQL,您如何从 "Persons" 表中选取所有的列?\

SELECT * FROM Persons

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8.通过 SQL,您如何从 "Persons" 表中选取 "FirstName" 列的值等于"Peter" 的所有记录?\

SELECT * FROM Persons WHERE FirstName='Peter'

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9.通过 SQL,您如何从 "Persons" 表中选取 "FirstName" 列的值以 "a" 开头的所有记录?
错误答案:SELECT * FROM Persons WHERE FirstName='a'\

正确答案:SELECT * FROM Persons WHERE FirstName LIKE 'a%'

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10.请判断下列说法是否正确:当所列出的某个条件为 true 时,OR 运算符会显示记录。当列出的所有条件为 true 时,AND 运算符会显示记录。\

正确

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11.通过 SQL,您如何在表 Persons 中选择 FirstName 等于 Thomas 而 LastName 等于 Carter 的所有记录?
错误答案:SELECT * FROM Persons WHERE FirstName LIKE 'Thomas' AND LastName LIKE 'Carter'\

正确答案:SELECT * FROM Persons WHERE FirstName='Thomas' AND LastName='Carter'

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12.通过 SQL,您如何按字母顺序选取 Persons 表中 LastName 介于 Adams 和 Carter 的所有记录?
错误答案:SELECT * FROM Persons WHERE LastName>'Adams' AND LastName<'Carter'\

正确答案:SELECT * FROM Persons WHERE LastName BETWEEN 'Adams' AND 'Carter'

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13.哪条 SQL 语句可返回唯一不同的值?

错误答案:SELECT UNIQUE\

正确答案:SELECT DISTINCT

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14.哪个 SQL 关键词用于对结果集进行排序?\

ORDER BY

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15.通过 SQL,您如何根据 "FirstName" 列降序地从 "Persons" 表返回所有记录?
错误答案:SELECT * FROM Persons ORDER FirstName DESC\

正确答案:SELECT * FROM Persons ORDER BY FirstName DESC

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16.通过 SQL,您如何向 "Persons" 表插入新的记录?
错误答案:INSERT VALUES ('Jimmy', 'Jackson') INTO Persons\

正确答案:INSERT INTO Persons VALUES ('Jimmy', 'Jackson')

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17.通过 SQL,您如何向 "Persons" 表中的 "LastName" 列插入 "Wilson" ?
错误答案:INSERT ('Wilson') INTO Persons (LastName)\

正确答案:INSERT INTO Persons (LastName) VALUES ('Wilson')

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18.您如何把 "Persons" 表中 "LastName" 列的 "Gates" 改为 "Wilson" ?
错误答案:UPDATE Persons SET LastName='Wilson' INTO LastName='Gates'\

正确答案:UPDATE Persons SET LastName='Wilson' WHERE LastName='Gates'

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19.通过 SQL,您如何在 "Persons" 表中删除 "FirstName" 等于 "Fred" 的纪录?\

DELETE FROM Persons WHERE FirstName = 'Fred'

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20.通过 SQL,您如何返回 "Persons" 表中记录的数目?\

SELECT COUNT(*) FROM Persons