添加字段时的语法错误

Question

以下代码适用于平均

 select
 [state], areatype, area, '00' [period], indcode, ownership, 
 avg(sites) sites, avg(employment) employment
 from dbo.tablename
 group by [state], areatype, area, indcode, ownership;

我保持简短和简单，以便学习这个概念。我在第二行和第五行添加了两个字段，现在出现语法错误。提供任何见解？

 select
 [state], areatype, area, periodyear, '00' [period], indcodetype, indcode, ownership, 
 avg(sites) sites, avg(employment) employment
 from dbo.tablename
 group by [state], areatype, area, periodyear, incodetype, indcode, ownership;

Msg 102, Level 15, State 1, Line 2
Incorrect syntax near 'sites'.

Answer 1

由于我无法解释的原因，我一次添加一个元素并且它正在工作。如果我输入全部，我会得到语法错误，但如果我开始使用的是什么，一次添加一个项目并执行，它就可以了。