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近来看到不少由于不规范字段名产生了诸多问题,现总结如下:
Excel中的列在数据库中称为:字段(或叫属性),行称为:记录(或叫无组)
打开Excel,在第一行输入:1,2,A,B,A/B 在第二行输入:100,200,300,400,500
这时我们就创建了一张字段为:1,2,A,B,A/B 记录为:100,200,300,400,500 的表,其结构如下:
现在我们来进行以下SQL查询
[code=sql]SELECT [1] FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT 1 FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT [2] FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT 2 AS T FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT 1+2 FROM [Sheet1$] [/code]
运行结果为:
[code=sql]SELECT [1]+[2] FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT A FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT 'A' FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT B FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT 'B' AS T FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT A/B FROM [Sheet1$][/code]
运行结果为:
[code=sql]SELECT [A/B] FROM [Sheet1$][/code]
运行结果为:
通过以上实例你都发现了什么?
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