Nowadays, monitoring is a mixture of tools, systems, and codes—making it a very complex process. And with this complexity, comes variables for failure. Get DZone’s new Guide to Performance to learn how to proactively find these variables and solve them before a disruption occurs.
Course Of The Month
7 days, 12 hours left to enrollBecome a Premium Member and unlock a new, free course in leading technologies each month.
Solved
ODBC in C++: Need row count on SELECT query
Posted on 2007-11-21
When you prepare and execute a SQL statement, but before you fetch the results, is there any way to know how many rows there are in the result set? I need to create an array with the same number of elements.
Here's the application flow:
Execute SQL statement.
Bind columns to vars.
<-- I need the row count here so I can make an array of n elements.
Fetch rows.
The ODBC API has a function called SQLRowCount(), but MSDN says it only returns the number of rows affected by insert, update, or delete queries. It mentions nothing about select queries. I know I can read the entire result set to get the count, reset the cursor, and then read it again, but that is just inefficient.
Any ideas?
Here's the application flow:
Execute SQL statement.
Bind columns to vars.
<-- I need the row count here so I can make an array of n elements.
Fetch rows.
The ODBC API has a function called SQLRowCount(), but MSDN says it only returns the number of rows affected by insert, update, or delete queries. It mentions nothing about select queries. I know I can read the entire result set to get the count, reset the cursor, and then read it again, but that is just inefficient.
Any ideas?
[X]
Welcome to Experts Exchange
Add your voice to the tech community where 5M+ people just like you are talking about what matters.
- Help others & share knowledge
- Earn cash & points
- Learn & ask questions
3 Comments
>>I need to create an array with the same number of elements.
I recommend using a vector container, so that you don't need to know the number of elements needed for the array.
A std::vector container will grow to the size you need it, as you add elements to it.
It's also a safer approach over using new or malloc, since the vector will automatically clean up the memory.
I recommend using a vector container, so that you don't need to know the number of elements needed for the array.
A std::vector container will grow to the size you need it, as you add elements to it.
It's also a safer approach over using new or malloc, since the vector will automatically clean up the memory.
Featured Post
Question has a verified solution.
If you are experiencing a similar issue, please ask a related question
Suggested Solutions
| Title | # Comments | Views | Activity |
|---|---|---|---|
| SQL Server Agent "Access Denied" Error | 3 | 35 | |
| TDE for SQL Web Edition | 1 | 37 | |
| Need split for SQL data | 4 | 34 | |
| SQL 2008 - Find rows where only a specified field value exists for all rows with the same ID | 7 | 15 |
Why is this different from all of the other step by step guides? Because I make a living as a DBA and not as a writer and I lived through this experience.
Defining the name:
When I talk to people they say different names on this subject stuff l…
This article explains how to reset the password of the sa account on a Microsoft SQL Server. The steps in this article work in SQL 2005, 2008, 2008 R2, 2012, 2014 and 2016.
Via a live example, show how to backup a database, simulate a failure backup the tail of the database transaction log and perform the restore.
The viewer will learn how to user default arguments when defining functions. This method of defining functions will be contrasted with the non-default-argument of defining functions.
Suggested Courses
Course of the Month7 days, 12 hours left to enroll
737 members asked questions and received personalized solutions in the past 7 days.
Join the community of 500,000 technology professionals and ask your questions.