topic Re: Need help with writing data to the table in SQL server express 2012 database using labview in LabVIEW

Need help with writing data to the table in SQL server express 2012 database using labview

manny09 — Fri, 14 Jun 2013 15:24:27 GMT

I am new to using Databases with Labview.

I am trying to write some data to the table I made in database of SQL server express 2012 using Labview. I am using the "DB tools Insert Data.vi" to insert some random data to the table. But when I try to enter some data through the front panel, it doesn't let me write anything.

To keeps things simple for now, I am just using 1 column in the table and just writing any to that column. Could anyone point out what I am doing wrong or how I can solve this issue?

I have also attached the sample VI I made for this.

Thanks

Re: Need help with writing data to the table in SQL server express 2012 database using labview

BTC_Admin — Fri, 14 Jun 2013 16:22:36 GMT

You haven't connected data type connector on DB tools Insert Data.vi... what type of data are you trying to write to the table? You will need to specify that first. I can't tell if you mean that you see a "broken arrow" prohibiting you from running the vi or if there is some other issue. If you are familiar with database calls, communicating from LabVIEW isn't any different - those built-in functions are simply making such calls to the database on a lower-level (in fact there are even freeware toolkits for database connectivity that you can find on this site through search or on Lavag.org and look inside such toolkit functions to understand what is being done.) Mind you - data type you use must match what you have specified for that field in your database table.

-DP

Re: Need help with writing data to the table in SQL server express 2012 database using labview

Ranjeet_Singh — Sat, 15 Jun 2013 04:22:11 GMT

Can you attach 2011 format of your VI.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

manny09 — Mon, 17 Jun 2013 15:11:10 GMT

Thanks Guys,

I was able to find the solution.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

dzehner2 — Wed, 27 Aug 2014 17:47:44 GMT

What was your solution? I'm having the same issue.

I'm trying to create a table of accelerometer data using the Database Logging example VI. I've attached the VI I'm working with so you can help me step through this... If you look under the "Acquire Data" heading, you'll see a while loop that contains the database logging code I'm having trouble with. I've created a .udl file that successfully connects to the SQL server I want to write my data to, but I can't seem to get it to create a table and write my data to it. I've used my number of samples as the input for the number of rows in the table, and my sample clock timing as an input to the Wait function for the while loop iterations.

Any ideas? I'm stuck...

Re: Need help with writing data to the table in SQL server express 2012 database using labview

nyc_(is_out_of_here) — Wed, 27 Aug 2014 19:16:32 GMT

@dzehner2 wrote:

What was your solution? I'm having the same issue.

I'm trying to create a table of accelerometer data using the Database Logging example VI. I've attached the VI I'm working with so you can help me step through this... If you look under the "Acquire Data" heading, you'll see a while loop that contains the database logging code I'm having trouble with. I've created a .udl file that successfully connects to the SQL server I want to write my data to, but I can't seem to get it to create a table and write my data to it. I've used my number of samples as the input for the number of rows in the table, and my sample clock timing as an input to the Wait function for the while loop iterations.

Any ideas? I'm stuck...

No clue. Don't have LabVIEW 2014.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

dzehner2 — Wed, 27 Aug 2014 20:23:12 GMT

Re: Need help with writing data to the table in SQL server express 2012 database using labview

manny09 — Wed, 27 Aug 2014 20:47:32 GMT

Sorry. I don't have Labview 2014, so can't open your VI

Re: Need help with writing data to the table in SQL server express 2012 database using labview

dzehner2 — Wed, 27 Aug 2014 21:00:00 GMT

Here's the portion of the VI that handles the data exchange with the SQL server. I can post other areas of the VI if that will help. The wait function is using my sample rate and total number of samples to determine when to send the data to the server. The integer input into the table comes from the total number of samples (so it will create 1 table row for each sample).

Re: Need help with writing data to the table in SQL server express 2012 database using labview

nyc_(is_out_of_here) — Wed, 27 Aug 2014 21:06:37 GMT

Right now, your code has boolean set to False for creating a table.

Yet in your first post, you write that you want to create a table.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

Dennis_Knutson — Wed, 27 Aug 2014 21:09:13 GMT

None of that makes any sense. The wait is not required, nor the while loop. If it works at all, it would just keep writing the same data over and over again. What is the actual data type in the cluster? I suspect you need a for loop to write each row.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

manny09 — Wed, 27 Aug 2014 22:22:53 GMT

If you are planning to write a lot of data and really fast into SQL table, You should make the VI in 2 steps.

Step 1: Write the data to a text file

Step 2: Read from text file and write to the SQL table.

The reason being that you cannot write really fast and lot of points from labview to SQL. You will loose half of the points in the process.

When you write to the text file, its way faster and you have all the data secured. Then you can run the other part and it might take like 5 mins approximetly (depending on the number of points you are reading) to send the data to SQL.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

manny09 — Wed, 27 Aug 2014 22:30:43 GMT

I have attached an example for reading from text file to SQL. Maybe that helps

Re: Need help with writing data to the table in SQL server express 2012 database using labview

Dennis_Knutson — Wed, 27 Aug 2014 23:01:41 GMT

I've been using the database toolkit since before it was owned by NI and have never lost data or had to resort to writing to a file.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

dzehner2 — Thu, 28 Aug 2014 12:06:23 GMT

@Dennis_Knutson wrote:
None of that makes any sense. The wait is not required, nor the while loop. If it works at all, it would just keep writing the same data over and over again. What is the actual data type in the cluster? I suspect you need a for loop to write each row.

The actual data type is DBL, it's just acceleration in g. I had the wait and the while loop in there from the example on continuous logging, but I had suscpicions it wasn't really necessary.

Re: Need help with writing data to the table in SQL server express 2012 database using labview

dzehner2 — Thu, 28 Aug 2014 12:07:57 GMT

@manny09 wrote:

I have attached an example for reading from text file to SQL. Maybe that helps

Let me just make sure I understand your VI... You write to a text file, and then call that file name into the loop that connects to your SQL server and insert it into a table? That would work... I'll give it a shot!

Re: Need help with writing data to the table in SQL server express 2012 database using labview

mikeporter — Thu, 28 Aug 2014 13:21:27 GMT

First off, you only have to create the table once -- ever. While you can do that in LV, you will hardly ever want to.

Second, the DCT will make life infinitely more difficult for you. The process for inserting data into a database is really very easy and the DCT does an excellent job of hiding that simplicity beneath a complex, proprietary interface.

Check out this thread for most of what you need to know to use databases easily -- including some free drivers.

Mike...