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Hi
I have an access database and i want to make this setup.
This setup will be install in a laptops or in a servers.
There are different ways to do this? and how can i make access database setup?
this database will be used from my c# project that i also make
setup.
I also understand that i must make database setup because when i try to run my project setup an error has occurred.
the error is :
---------------
Execute reader requires an open and available connection.The connection's current state is closed.
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That error has nothing to do with creating a setup for the database. You don't have to make a seperate setup for the Access database. It's just a file.
That error means that you tried to use a connection to the database that you never opened. You have to open the connection and THEN you can read from it. It's a bug in your code...
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i solve the error. i must include in my application folder the access file now it's ok ..
i have another question:
If i want to run my project access database from a server i have to make more work about it?
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You can NOT put the database in the application folder under Program Files. Everything under Program Files is readonly by default. Admins don't like giving write permissions to anything under that folder.
Put your database in a more suitable location.
But, no matter where you put it, you'll have to change your applications connection string to tell it where to find the file.
If this is going to be a shared database used by more than one person, you really do NOT want to use an Access database.
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the database will be use by minimum 3 person but this is not my decision i only follow instructions
from others.
because i don't make setup in previous times that must be in a server,
it is my first time.
Can you please tell me or give me some examples about how make setup access database that have to be save in a server??
thnx
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There's nothing to setup for an Access database. You just copy the .MDB file to wherever it needs to go.
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Let me add some reinforcement to Dave, DO NOT USE ACCESS AS A SERVER database, convert to SQL Server. Access is a single user database, Microsoft states this in the documentation. You should not be using for shared data. BTW SQL Server express is FREE, no charge unless you require more than 4gb at which point you need to get a server licence.
Never underestimate the power of human stupidity
RAH
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It really depends how your application is connecting your .MDB?
If your application assumes the ms access database to be a specific folder like Application Installation folder, then you can follow below link <a href="http://vijirajkumar.blogspot.in/2010/03/create-setup-and-deployment-project.html">http://vijirajkumar.blogspot.in/2010/03/create-setup-and-deployment-project.html</a>[<a href="http://vijirajkumar.blogspot.in/2010/03/create-setup-and-deployment-project.html" target="_blank" title="New Window">^</a>] and to attach your 'Access' database: In the figure 4 of above tutorial -> right click on 'Application Folder' -> select 'File...' and then search the *.mdb file on your hard disk. When you compile (Debug or Release) it will copy the database to the App Folder.
While installation it will be copied to user’s application installation folder (i.e C:\Prog Files\xyz…)
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zebra88 wrote: this database will be used from my c# project that
MS Access requires that the OS must have file level access to the database file.
So if you want 3 people (three different computers running the client app) to use it then all three of those must have the file viewable via Explorer.
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Hi All
1. I have GridEX which bound to DataSet
2. One of the column is ceckbox cloumn
3. I fileter one of the column (not the ceckbox column) by the header column and I see the correct data in the Grid
4. I want to checked only the filtered record (the record which shown in the grid) how can I do it?
until now I Loop on all of the records in the dataset and checked all the records and finally refresh the grid
any advice
Thanks
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I get the basic parts of incrementing and decrementing a variable by one.
Maybe because I'm not quite thinking like a programmer yet, is why I don't understand this code below.
"Console.WriteLine(y); // result = 99 — The value of y after" - this is what's confusing me. How do you get 99 when there is no loop?
And
doesn't 100 become 99 before you add it to 10?
Of course after compiling this, it worked. It came from a book from BrainMeasures dot com. They said the book was even for novices (PSSH)
Dummy it down for me quite a bit please.  LOL
<pre lang="c#">using System;
class ArithmeticOperators
{
public static void Main()
}
int x = 10;
int y = 100;
int z = y-- + x;
Console.WriteLine(z); // result = 110
Console.WriteLine(y); // result = 99 — The value of y after
// decrementing
z = --z + x;
Console.WriteLine(z); // result = 119
}
}</pre>
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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WidmarkRob wrote: How do you get 99 when there is no loop
Why do you think that you would need a loop to add or subtract anything?
WidmarkRob wrote: y--
The '--' is a post decrement operator that is what is decrementing 100 to 99.
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y = 100;
Also when the console.writeline(y);
that should be 100, shouldn't it?
It is declared at 100.
I would probably understand the answer if it was written like this "console.writeline(y--);
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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WidmarkRob wrote: It is declared at 100.
Yes the initial value is 100, did you see the y--? As you were told, the -- is the decrement
operator that makes y 99. The -- is short hand for y = y - 1.
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did you see the part where I said I would understand if it was written the other way?
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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WidmarkRob wrote: did you see the part where I said I would understand if it was written the other way?
Yes I saw that. That line of code would print 100 so it would not help you understand why y is 99 at all.
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"Console.WriteLine(z); // result = 110"
After reading the book, that line right there makes sense to me.
It said something similar to, "you evaluate the expression before you do that decrement".
I get that part, the way the expression was written I understand that.
So when we write the next line to the console, "Console.WriteLine(y);"
the variable y automagically turned into 99?
y is declared at 100. I just don't see how it could automagically turn into 99 without some sort of loop.
y-- is used in an expression, not used as a declared variable.
I think that's where I'm getting confused.
Maybe I've just seen too many YouTube videos where they are using incrementing and decrementing with loops.
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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WidmarkRob wrote: the variable y automagically turned into 99?
But it is not automagically turned in to 99 that is what the decrement operator does! And that is what I have been telling you.
Take your code:
int z = y-- + x;
Substitute your values
int z = 100-- + 10;
The value of z is calculate right?
100 + 10 = 110 right? The then post decrement operator is applied to y so
y = y - 1 which make
y = 99 .
Still not sure why you would think that you would need a loop to add or subtract anything.
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ThePhantomUpvoter wrote: The -- is short hand for y = y - 1
That's not entirely correct.
The point behind the '--' being in front of the expression or behind it just tells the compile WHEN to increment or decrement the expression. The operation is either going to happen before the expression is evaluated, in his case y, or after.
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WidmarkRob wrote: Dummy it down for me quite a bit please.
OK, let's break it down.
WidmarkRob wrote: int x = 10;
x is now 10.
WidmarkRob wrote: int y = 100;
y is now 100. Pretty obvious so far.
But this
WidmarkRob wrote: int z = y-- + x;
is a weird thing, and in order to understand it, it is necessary to understand the difference between the result of an expression and the effect of an expression. The C# rules say this about post-decrement: "the operand is decremented. The result of the expression is the value the operand had before the decrement". (see operator --[^])
So what's happening here is that y is decremented (that is the effect), so after y-- has been evaluated y will be 99, but the value is the old y, 100 (that is the result). Then it goes on to add x to that result, no surprises there.
WidmarkRob wrote: z = --z + x;
This is different, a pre-decrement as it is called. The value of a pre-decrement is the new value, ie after the decrement.
ps: most of this applies to most C-derived languages, except that C# is a bit special in that it specifies that the side-effects happen from left to right. That only matters if you decrement or increment something, and then use that same thing again in the same expression (ok not really, it's more complex, but it's True Enough)
modified 28-Apr-13 7:54am.
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Okay, I think I got it now.
When the decrementing comes after the variable.
We evaluate the expression before the decrementing is applied.
Then whenever we use the old declared variable after that first evaluated expression, the decrementing is applied.
Is that right?
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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Close enough. The decrementing itself really happens while that expression is being evaluated, but that rarely matters. It does matter if you do this:
int x = 0;
int z = x++ + ++x; After that, clearly x is 2, because it was incremented twice.
And z is also 2, proving that the increment really happens while the expression is evaluated. First x++ is evaluated, the result is 0 and the effect is that x is now 1. Then ++x is evaluated, x was 1 and for pre-increment the result is the value after the increment, so the result is two (the effect is again that x is incremented, of course). So that works out to 0 + 2.
The left-to-right rules goes even further, if you have an assignment where there's an increment on the left hand side (yes, you can do that), it happens before the right hand side is evaluated, which can be demonstrated with something like this:
int[] array = new int[2];
int x = 0;
array[x++] = x++; After that, x is 2, obviously, and array looks like this: { 1, 0 }
What happened, was the first x++ was evaluated first, making the index into the array 0, then the right hand side is evaluated, which is 1 due to the first increment, and then x is incremented again, and finally the value of the right hand side (which was 1) is stored in the array at index 0.
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Because I'm Just Beginning, I'm going to stop at "Close Enough".
I'm sure the book will eventually got into more details, but… For now, as long as they understand that basics.
I think I can move on.
Thank you for helping me understand this more, actually way mor. 
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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after all that dumbing it down, I'm thrown for a loop (pun intended).
After reading a little bit more in the book they decide to give me a little exercise.
int x = 10;
int y = 100;
int z = y;
y = y++ + x;
z = ++z + x;
I thought I would do this in my head before writing it to the console window.
The first expression, the answer I got my head was:
110
(which turned out to be right, woo hoo)
The second expression I got wrong, in my head I came up with:
121
the console window printed out:
111
Console.WriteLine(y);
Console.WriteLine(z);
just before this exercise, the book showed me a table trying to explain:
primary, urnary, binary
<a href="http://www.widmarkrob.com">My Coding Journey</a>
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WidmarkRob wrote: int z = y;
Ok, what happens here is not "make x an other word for y", which is what I think you might have thought. It really means "let x have the value that y now has".
y later changed, z did not.
Ok z did change, but the assignment to y did not affect it.
WidmarkRob wrote: y = y++ + x;
does not affect z, only y.
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