什么是GQL计数查询 [英] what is the GQL count query

问题描述

为了时间的利益，我的意思是GQL，如

  SELECT * FROM Song WHERE composer ='Lennon， John'
  

以下失败

  SELECT COUNT（*）FROM myEntity 
  

也包含以下内容

  SELECT COUNT（）FROM myEntity 
  

解决方案

如图所示 here ，实际上有一种方法来计算你的GQL的回报。有关GQL的文档语言显示您无法真正进行统计在查询本身。所以你要做的就是把你的select *放到一个GQL查询对象中，然后调用该对象上的count（）方法来计数

In the interest of time, I do mean GQL, as in

SELECT * FROM Song WHERE composer = 'Lennon, John'

The following failed

SELECT COUNT(*) FROM myEntity

also the following

SELECT COUNT() FROM myEntity

解决方案

As shown here, there is actually a way to count the return of your GQL. The doc about the GQL language shows you can't really do a count on the query itself. So what you would do is take your select *, put it in a GQL query object, then call the "count()" method on that object to have the count

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