vc ++ MFC中select查询的where子句的语法 [英] syntax for where clause of select query in vc++ MFC

问题描述

我在vc ++ 12 MFC中实现Project。后端是访问数据库。我想将一行中的所有四列值选择为四个变量。



我的查询是：

 m_txt =  选择CompanyName为m_CompanyName，Model为m_Model，OrderNo为m_OrderNo，StreetAddress为m_StreetAddress，Phone为m_Phone，Logo来自公司的lg1  

我也想知道如何在这里指定where子句

 m_txt =   select CompanyName as m_CompanyName ，Model as m_Model，OrderNo As m_OrderNo，StreetAddress As m_StreetAddress，Phone As m_Phone，Logo As lg1 from Companies其中CompanyName = + s1; 

这就是我们在MySql或Sql server中编写查询的方式，s1是字符串类型的变量，但在vc ++ at + sign中它给出了错误。



please帮助，非常urjent

解决方案

这是的副本选择查询以在vc ++中选择数据到变量 [ ^ ]，我已经回复了。请不要重新发布同样的问题，它只是为人们重复工作。



而且，不，这不紧急。

正如我在问题的评论中提到的，你需要做的就是连接字符串！



回到C ++基础知识！



另一方面，这是一个关于使用Native C或C ++开发Access 2007解决方案 [ ^ ]

如何使用VBA / C ++ / Java调用参数化ADO查询 [ ^ ]



更多资源：

Visual C ++中的数据访问 [ ^ ]

< a href =http://www.codeproject.com/KB/database/readdb.aspx>使用CDatabase类读取Access数据库 [ ^ ]

检索，编写和创建Microsoft Access文件（CDaoDatabase和CDaoRecordset）中的数据 [ ^ ]





下次，请使用改善问题小部件，而不是发布另一个小部件。

I am implementing Project in vc++ 12 MFC. back-end is access database. I want to select all four columns values in one row into four variable.

My query is:

m_txt = "select CompanyName As m_CompanyName, Model As m_Model, OrderNo As m_OrderNo, StreetAddress As m_StreetAddress , Phone As m_Phone, Logo As lg1 from Companies 

and I also want to get know how to specify where clause here as

m_txt = "select CompanyName As m_CompanyName, Model As m_Model, OrderNo As m_OrderNo, StreetAddress As m_StreetAddress , Phone As m_Phone, Logo As lg1 from Companies where CompanyName="+s1;

That's how we write query in MySql or Sql server, s1 is variable of string type but in vc++ at + sign it gives error.

please help,it is very urjent

解决方案

This is a duplicate of select query to select data into variable in vc++[^], which I already responded to. Please do not repost the same question, it just duplicates work for people.

And, no, it is not urgent.

As i mentioned in the comment to the question, all you need to do is to concatenate string!

Go back to C++ basics!

On the other hand, here is a tutorial about Developing Access 2007 Solutions with Native C or C++[^]
How To Invoke a Parameterized ADO Query Using VBA/C++/Java[^]

More resources:
Data Access in Visual C++[^]
Using the CDatabase class to read an Access databases[^]
Retrieving, Writing, and Creating Data in a Microsoft Access File (CDaoDatabase and CDaoRecordset)[^]


Next time, please use "Improve question" widget instead posting another one.

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