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I am new to VB.net but have been doing ok developing a personal project so far.... since yesterday... The problem is that I got stuck when trying to read the row count of a datagrid that has more than 1500 rows filled with data. The result that I am getting is form2.datagridview1.rows.count - 1 = -1. Which makes no sense since the datagrid is plenty of rows.
Something that I must say is that this datagrid belongs to form2 (a second form that pops-up and shows the datagrid when I call it from From1).
Any thoughts on what could be possibly happening?
Thanks for any advice or comment on this matter.
PS: I'll post my code as soon as I get home
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Actually what I want is to perform a reverse loop search from the last row of the datagrid to the first one.
When I try to obtain the las row index, I always get zero....
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Can you copy/paste the code into your message, formatted with PRE tags?
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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I just figured out that I had to connect again to the database and count the rows of a new created dataset.
I was getting 0 rows because even if the datagrid was full of data, that data came from a previously created dataset that was no longer available. So I really was referencing to a "empty" datagrid.
Problem solved.
Thank you.
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I have an Access database for which I'm trying to write a query based on a request from the users.
I have a table of data related to artwork, with three columns: ArtworkId, DescriptionText, and CalloutNumber. Each piece of artwork can have more than one DescriptionText value.
What would be a good way to write an SQL query to return, for example, all ArtworkId records having both DescriptionText = "Start Switch" and DescriptionText = "Stop Switch" records?
ArtworkID / DescriptionText
123 / Motor
234 / Fuse
234 / Start Switch
456 / Stop Switch
789 / Start Switch
789 / Stop Switch
789 / Light
Result = ArtworkID 789
Any assistance will be greatly appreciated. Thanks!
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I think the follow query would do what you want:
SELECT ArtworkID
FROM Artwork
WHERE DescriptionText In ("Start Switch","Stop Switch")
GROUP BY ArtworkID
HAVING COUNT(*)=2;
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Thanks. I tried something similar this afternoon, but it didn't work. I'll try your idea tomorrow.
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Just happens to work with the example data given. It will show wrong results with duplicated entries, e.g. having two times 357,"Start Switch".
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You are right. If for some reason you can't prevent duplicate entries, then you can use the following query:
SELECT ArtworkID
FROM (SELECT DISTINCT ArtworkID, DescriptionText FROM Artwork) as t1
WHERE DescriptionText In ("Start Switch","Stop Switch")
GROUP BY ArtworkID
HAVING COUNT(*)=2;
It uses a sub-query to get the distinct values first. The rest functions just the same.
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For reasons unknown, this didn't work. My intention was for the search text entries to more resemble wildcard text. For example, return all IDs with "switch" or "cable" or whatever in the DescriptionText field.
Thanks for your response.
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You must join the table with itself. Something like:
SELECT a.ArtworkID
FROM Artwork a
INNER JOIN Artwork b
ON a.ArtworkID=b.ArtworkID
WHERE a.DesciptionText="Start Switch" AND b.DescriptionText="Stop Switch"
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Well, that worked. I used 'like' for '=' and surrounded the search text with '%' characters.
Now, suppose I wanted to search using up to 5 terms - would I have to nest the inner joins?
This seems really complicated for something I can see with my eyes & describe easily using English words.
(Also, I tried using the Filter By Form command, but it wouldn't work with my form.
Thanks for the feedback.
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Surely there's an easier way, but this is how I got it to work (I've updated the table and field names):
SELECT *
FROM art_callout_table
WHERE artboardnumber IN (
SELECT artboardnumber FROM art_callout_table
WHERE artboardnumber IN (
SELECT artboardnumber FROM art_callout_table
WHERE lrutext LIKE "%start%")
AND lrutext LIKE "%light%")
AND lrutext LIKE "%switch%";
What confused me repeatedly during development, and what confused the users (they were expecting the search to work one way & I was assuming it to work another), is that there are two distinct search methodologies:
1) Using the built-in Access table filtering commands (or a basic SELECT FROM WHERE statement) to narrow down a table of description text values. Repeated filters can be applied to narrow the list further, but if you're looking for "switch" and "start", all you'll get is individual description text records having both values, eg "big red starting switch" or "switch start light" but not "green switch". Not terribly helpful.
2) Use a different search technique to return all ArtworkID values which have "switch" or "start" or "light" strings within their DescriptionText fields, eg don't look just for DescriptionText records similar to "switch start light blinker".
I thought this was going to be much easier than it turned out to be. Thanks all for your help.
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Good you solved it! 
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In a LAN i am having a database on SQL Server express edition.I want to fetch data from this server on some other machine in the same LAN.
I have already done setting in server for allowing remote connections and allowing the firewall setting. etc.
Can anyone tell me from scratch what I have to do on the client PC to fetch data on it in VBA.
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You can do that using ADO. Create an ADO connection to the remote server and use the ADO recordset objects to retrieve data.
Make sure you have included a reference to ADO (ActiveX Data Objects) in your VBA project.
HTH
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in the project i want to build, i already have a school results system and students should be able to request their results via sms.thus by sending their stud. id to the system number(gsm modem number) and the system automatically reading the message, extracting the stud. id and year from the message search the results table for the results and send it back to the student who requested for the results(senders number) i will also store requests to the database
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..cool - and what is your question?
If you're stuck with a particular task, then we can help. As is, you only mentioned that you're about to do a project. If you're looking for volunteers, you'd need to open-source it first. Or try the collaboration-forum 
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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You might want to store the cell phone numbers of your students in the db and the incoming message would just be RESULTS. They should not send their student ID. You want to prevents Student A from requesting results for Student B.
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Come on! You know security is the ultimate afterthought. 
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David Mujica wrote: You might want to
I'm not gonna build it  But good point
Bastard Programmer from Hell
if you can't read my code, try converting it here[^]
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Eddy Vluggen wrote: what is your question?
Can't you tell from the subject line?
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TL;DR
Bastard Programmer from Hell
if you can't read my code, try converting it here[^]
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I'm writing a suite of software of which one of the programs is client that connects to a server; the client performs actions of behalf of request from the server with both the client and server being windows services.
For the server I need it to store data such as user names, password (actually hashes of passwords), permission settings, etc. I don't want the information stored on our SQL server because other employees have access to it and there is a risk of information being changed, deleted, and it won't be secure for this purpose. I also don't want the data stored on the server is a file (such as a .DAT file) because again other employees have access to the server and there are the same concerns as with the SQL server.
I was trying to find a way to save information internally within the program. I've worked with embedded resources, but only to the extent of extracting an embedded Word template and saving it to folder. I'm assuming there would be a way I could extract some sort of compressed XML file, change the data I need to, and then re-embedding it using a MemoryStream so the file is never written to the HDD. Would this be a way to go? Any body know any good articles explaining the process of extracting and embedding file, changing it, and then re-embedding it?
The company is a small company and over the course of a day I'm estimating that the server service would have to do the extract/re-embedding maybe 20 times so I don't see it being very heavy on resources. However I'm open to any other ideas. My only requirements is no SQL server or local file, secure, and the data is persisted across system restarts.
Thanks in advance for any help, ideas, or suggestions anybody can provide.
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