4.1.5. Comments

4.1.5. Comments

4.1.5. 注释

A comment is a sequence of characters beginning with double dashes and extending to the end of the line, e.g.:

以两个-开头的整行，都是注释，例如：

-- This is a standard SQL comment

Alternatively, C-style block comments can be used:

当然，C类型的块注释也可以使用：

/* multiline comment

* with nesting: /* nested block comment */

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*/

where the comment begins with /* and extends to the matching occurrence of */. These block comments nest, as specified in the SQL standard but unlike C, so that one can comment out larger blocks of code that might contain existing block comments.

/*与*/之间的均为注释。 按照SQL标准的规定，这些块注释嵌套，但与C不同，因此可以注释掉可能包含现有块注释的较大代码块。

A comment is removed from the input stream before further syntax analysis and is effectively replaced by whitespace.

在进行进一步的语法分析之前，将从输入流中删除注释，并有效地将其替换为空格。