如何从sqlite3中获取所选结果的行数?

How to get the number of rows of the selected result from sqlite3?(如何从sqlite3中获取所选结果的行数?)
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问题描述

我想获取所选行的数量以及所选数据.目前我不得不使用两条sql语句:

I want to get the number of selected rows as well as the selected data. At the present I have to use two sql statements:

一个是

select * from XXX where XXX;

另一个是

select count(*) from XXX where XXX; 

可以用单个sql字符串实现吗?

Can it be realised with a single sql string?

查看了sqlite3的源码,发现了sqlite3_changes()的函数.但该函数仅在数据库发生更改时(在insert、delete 或update 之后)有用.

I've checked the source code of sqlite3, and I found the function of sqlite3_changes(). But the function is only useful when the database is changed (after insert, delete or update).

谁能帮我解决这个问题?非常感谢!

Can anyone help me with this problem? Thank you very much!

推荐答案

试试这个方法

select (select count() from XXX) as count, * 
from XXX;

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