Question

我对我的怀疑有简短。

什么是正确的?

SELECT * FROM Persons WHERE Year= 1965

或

SELECT * FROM `Persons` WHERE `Year` =  1965

这是个人的选择,还是真的错了?

Answer 1

What if you have a table named table, or a column named where. These are reserved keywords. If you used those in your queries without backticks, they d produce an invalid query (Of course, using reserved keywords is bad practice).

SELECT something FROM table WHERE where = 1;

页: 1

SELECT something FROM `table` WHERE `where` = 1;

Answer 2

如果您的识别资料(栏目、表格名称、操作者等)含有MySQL保留词,则需要批量。

详见保留词的完整清单:。

Answer 3

Both are correct, but the second one will ALWAYS be accepted, even when you use keywords or functions like while and NOW() that would normally be seen as operators.

Answer 4

Both methods are correct, the single quotation mark indicates starts and endings of a string.

因此,如您使用像<代码”这样的一栏别。出生年份:,届时,您需要使用单一引标符号。

... WHERE `Birth year` = `1965`

However it is not recommended only use more then one word in the aliases.

正如@Cody Caughlan在你使用。

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