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It may not be perfect practice, but it's something quite useful - I keep several "odds and ends" in Excel format that should really be in SQL, and being able to transfer the data from the one to the other makes life a lot easier (I'm tidying up the code in my link at the moment, because it's pretty poorly written). Once I'm finished, I'll transfer half a dozen of my Excel sheets to SQL and convert the spreadsheets to C# forms instead.
I suspect it's not something he wants to do every day, but he wants to avoid the potential errors involved in a manual transfer. Thinking about it, I may knock up a utility to do it as well - prototyping the DB is a lot easier in Excel than in SSMS where you have to keep switching about to / from design mode.
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952)
Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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Ok, i can agree with it only in case when it happens once on a long time.
BTW: Both your answers have been upvoted!
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OriginalGriff wrote: and being able to transfer the data from the one to the other makes life a lot easier
Just to clarify... The OP was asking about creating a table not loading data.
So are you referring to creating tables or loading data?
And if you are creating tables are you referring to a standard business table or just something like an enumeration table?
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The way I read the OP's question he wanted to use a Excel Sheet to create a "standard" SQL table and populate it with the data - so my answer did just that. Mind you, he could just leave off the last stage if he doesn't want to transfer the data as well.
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952)
Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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So then you are creating tables from your spreadsheets...
How do you determine field sizes for numerics and text?
How do you determine what names to use for the fields?
How do you specify a primary key?
How do you specify indexes?
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Not too bad, really.
The fields sizes (or at least, safe field sizes) can be inferred from the datatypes Excel returns - have a look at the code at the bottom of the link in my original post, it works pretty well.
The names can be retrieved as the column names from SQL - and nearly everybody uses those!
You can't assign primary keys automatically - excel doesn't have the concept - so the table is going to need some manual post processing. To be expected I guess! Exactly the same with indexes and foreign key relationships etc. - again Excel doesn't know what they are.
But for getting the basic structure right, and filling it in, then transferring a working structure complete with sample data it's not a bad idea, and could well be a lot easier than the equivalent in SSMS (which tends to annoy me a lot more than it should if I tweak my data when I'm designing data storage  )
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952)
Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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Good morning wise ones.
You've probably seen DB code akin to this before:
public List<int> GetSomeNumbers()
{
List<int> x = new List<int>();
using (SqlConnection)
using (SqlCommand)
using (SqlDataReader)
while (reader.Read()) x.Add(reader[0]);
return x;
}
Which would populate and return a list from the first column of the query. I've left the detail out, and yes a cast would be required. Another possibly better approach would be this:
public IEnumerable<int> GetSomeNumbers()
{
List<int> x = new List<int>();
using (SqlConnection)
using (SqlCommand)
using (SqlDataReader)
while (reader.Read()) yield return reader[0];
return x;
}
The reason it might be better is because it immediately returns on each read so that if I do something like send the result straight over a network I can do this is a 'streaming' approach which would be faster and not require as much memory. The reason it might not be as good is that IEnumerable is inherently more confusing. The call doesn't even get invoked until something tries to iterate it and that can catch us all out.
I'm starting to adopt the latter approach more and more, but questions arise because of the more complicated execution flow. In particular, what happens if I do this:
foreach (int x in GetSomeNumbers())
{
if (x == 0) break;
}
This is the bit I'm unsure about. Assume that a zero arrives a long time before then end of the result set. IEnumerables tell us when we're at the end of can give us the next item, but what happens if the consumer bails out before the end? There's no way (that I know of) to tell the iterator function we've concluded. Where does this leave the disposal of the reader, command and connection?
Be happy, its Friday!
Regards,
Rob Philpott.
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Looking at section 8.8.4 of the C# Language Specification[^]:
A foreach statement of the form
foreach (V v in x) embedded-statement
is then expanded to:
{
E e = ((C)(x)).GetEnumerator();
try {
while (e.MoveNext()) {
V v = (V)(T)e.Current;
embedded-statement
}
}
finally {
}
}
Therefore, regardless of whether your statement block breaks the loop, throws an exception, or runs to completion, the enumerator object will always be disposed.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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Very nice answer Richard.
I had a feeling that IDisposable may be at work. Unfortunately I tend to think along the lines that an IEnumerable is merely something you iterate over rather than something that returns a disposable iterator (or enumerator if you prefer - I think the parlance is different for .NET than STL etc.)
So I guess what's happening now is the when the iterator gets disposed, it's essentially doing the same as a yield break to force its way out my own while loop. The implicitness of that bothers me slightly, because my condition of .Read() will always go to the end of the result set. And in fact the ability to break the loop is being delegated to outside.
I really should try all this out in the debugger. 
So that's cleared that up and I've got one less thing to worry about now. Thanks!
Regards,
Rob Philpott.
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 Nice Answer to allow ones learning for a friday thanks
Every day, thousands of innocent plants are killed by vegetarians.
Help end the violence EAT BACON
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Nice Question to improve ones learning for a friday thanks
Every day, thousands of innocent plants are killed by vegetarians.
Help end the violence EAT BACON
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Rob Philpott wrote: I can do this is a 'streaming' approach which would be faster and not require as much memory.
Of course if that is a concern then caching the results would be far better than either choice.
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I need to display data in gridview is Sharepoint Gridview is good control for that..
should i use it with Visual webpart or only webpart ?
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I am talking about SPGridView
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And what is your question?
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How to have windows app c# in adobe flash player? Like this link
[^]
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That's very interesting: I assume that's a simulation of a very complex .NET app; since, to my knowledge, you simply can't run a .NET App in Flash, or convert one to Flash.
But, the mind boggles: who would have the time to create such a simulation ?
I'd like to know how this was done, also !
“The best hope is that one of these days the Ground will get disgusted enough just to walk away ~ leaving people with nothing more to stand ON than what they have so bloody well stood FOR up to now.” Kenneth Patchen, Poet
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What makes you think that this is a windows app written in C#? I see nothing in there that indicates it is any such thing.
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But how to create such this
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"Learn Flash".
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
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What is it you want to create?
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It's not a Windows app. It's all Flash.
/ravi
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Hi im not sure if I can ask for help here, my appolagise if not I will remove if required to.
I am stuck however with a hangman style game I am building, Simply a word pulls from file at random and the output to the user is '*' symbols instead of the letters, the user can select to guess a letter from the keyboard etc... The program does cross ref the guess with the actual word and if the user guesses correctly it will replace the '*' with the correct letter, the issue is it will only do one loop so wont allow for continuation until the word is complete. I would appreciate any help with this so that the user keeps going until the word is completed. Many Thanks. Here is the code:
private void chckGss_Func(string wordToGuess)
{
StringBuilder showUser = new StringBuilder(fileWord.Length);
for (int i = 0; i < fileWord.Length; i++)
showUser.Append('*');
List<char> goodGuess = new List<char>();
List<char> badGuess = new List<char>();
int lives = 5;
bool win = false;
int charReveal = 0;
string inpt;
char guess;
while (!win && lives > 0)
{
inpt = tmpLttr.ToUpper();
guess = inpt[0];
if (goodGuess.Contains(guess))
{
btnCorrect.Visible = true;
lblCorrect.Visible = true;
continue;
}
else if (badGuess.Contains(guess))
{
btnWrong.Visible = true;
lblWrong.Visible = true;
continue;
}
if (wrd2GuessUpper.Contains(guess))
{
goodGuess.Add(guess);
for (int i = 0; i < fileWord.Length; i++)
{
if (wrd2GuessUpper[i] == guess)
{
showUser[i] = fileWord[i];
charReveal++;
}
}
if (charReveal == fileWord.Length)
win = true;
}
else
{
badGuess.Add(guess);
lives--;
return;
}
txtWrdToGuess.AppendText(showUser.ToString());
}
if (win)
MessageBox.Show("You win!");
else
MessageBox.Show("You lose, the word was " + fileWord);
}
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I think the problem is that return statement near the bottom. Replace it with a continue statement and I think it will work.
The difficult we do right away...
...the impossible takes slightly longer.
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