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how can u enumerate tables given a database?
btw, we use ADO for database access. and we use SQL server.
thanks!
norm
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Read my article called MSDEGUI - the queries I use there should work for you. It's in the new list on the main page.
No, I don't remember them, or I'd just tell you 
Christian
No offense, but I don't really want to encourage the creation of another VB developer. - Larry Antram 22 Oct 2002
Hey, at least Logo had, at it's inception, a mechanical turtle. VB has always lacked even that... - Shog9 04-09-2002
Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002
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just scan yr article briefly. isnt it for .NET?
anyway, i'm building all my code with VC6 - lots of anti microsoft types here in this company.
anyway, i am thinking, perhaps I can read MyDB.Tables.sysobjects
there're three columns of interests:
a. "names" -- object name: a simple string
b. "id" -- object id: just a simple integer
c. "xtype" and code as follows:
Object type. Can be one of these object types:
C = CHECK constraint
D = Default or DEFAULT constraint
F = FOREIGN KEY constraint
L = Log
FN = Scalar function
IF = Inlined table-function
P = Stored procedure
PK = PRIMARY KEY constraint (type is K)
RF = Replication filter stored procedure
S = System table
TF = Table function
TR = Trigger
U = User table
UQ = UNIQUE constraint (type is K)
V = View
X = Extended stored procedure
So, I will just count and retrieve an array of names (names - column one of sysobjects table) for all entries where xtype==U
norm
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norm wrote:
just scan yr article briefly. isnt it for .NET?
Yes, so ? The query remains the same, all that changes is the layer that is talking to SQL Server.
norm wrote:
anyway, i'm building all my code with VC6 - lots of anti microsoft types here in this company.
Has no-one told them it comes from Microsoft ? :P
norm wrote:
anyway, i am thinking, perhaps I can read MyDB.Tables.sysobjects
I suspect that is exactly what I did in the article I pointed you to.
Christian
No offense, but I don't really want to encourage the creation of another VB developer. - Larry Antram 22 Oct 2002
Hey, at least Logo had, at it's inception, a mechanical turtle. VB has always lacked even that... - Shog9 04-09-2002
Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002
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thanks chris. and i hope that there'll be a day when it's no longer hip just being an anti microsoft. it's so stupid.
norm
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If that day comes, it will be the day after Solaris penetrates 90% of the market.
Christian
No offense, but I don't really want to encourage the creation of another VB developer. - Larry Antram 22 Oct 2002
Hey, at least Logo had, at it's inception, a mechanical turtle. VB has always lacked even that... - Shog9 04-09-2002
Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002
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just remember in addition to cursor type, u can also specify whether you want server side cursor or client side cursor isnt it?
can u tell me where I should read up in this regard?
norm
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Dunno, a book on ADO ? O'Reilley have a good one, from memory.
Christian
No offense, but I don't really want to encourage the creation of another VB developer. - Larry Antram 22 Oct 2002
Hey, at least Logo had, at it's inception, a mechanical turtle. VB has always lacked even that... - Shog9 04-09-2002
Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002
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Simple solution - use OpenSchema method of ADO Connection object:
pConn->OpenSchema(adSchemaTables,vParams)
where vParams is a Safearray containing the following null, schema_name, null, null. This then returns a recordset which contains all of the tables in the schema. To enumerate the fields of a table, use similar:
m_pConn->OpenSchema(adSchemaColumns, vParams)
where vParams contains null, schema_name, table_name, null. Again returns recordset that can be used to get all sorts of information.
If you need a fuller example, fell free to e-mail me. vParams cna be used to control the operation in a much more detailed way than here, but this provides basic naming information.Also, has the advantage that will work with any DB type (SQLServer, Oracle, Access etc).
Hope it helps
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Hi, I have an CEdit control which can be resized. The user can switch from a single line edit control to a multi line control if he decides so.
How do I detect the number of lines (a CEdit can hold not actually has)? I need to catch the switch from a single - to multi line layout and change some atributes.
Thanks
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Do you mean visible lines in the edit control? There is no limit to the number of lines a control can have upto the 64K byte limit of \r\n pairs 63336/2 = 32768 possible lines held.
If its just the number of lines the control could display without a scrollbar, then you can compute this by gettting the client area size of the control, the DC and the font, and then count the number of lines like this:
int ComputeLines(int ID)
{
CWnd *pWnd = GetDlgItem(ID) ;
if (!pWnd)
return 0;
CEdit *pEdit = static_cast<CEdit*>(pWnd);
if (!pEdit)
return 0 ;
CDC *pDC = pEdit->GetDC() ;
CFont *pFont = pEdit->GetFont();
CFont *pOldFont = pDC->SelectObject(pFont);
CRect rect ;
pEdit->GetCLientRect(&rect);
CSize size = pDC->GetTextExtent("A", 1);
pDC->SelectObject(pOldFont);
ReleaseDC(pDC);
return rect.Height() / size.cy;
}
OK, the above it untested and types directly so, it may, may not work correctly
Roger Allen
Sonork 100.10016
I have a terminal disease. Its called life!
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Roger Allen wrote:
If its just the number of lines the control could display without a scrollbar, then you can compute this by gettting the client area size of the control, the DC and the font, and then count the number of lines like this:
thousand thanks, Roger! 
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PS: instead of GetDC/ReleaseDC I might better use a CClientDC(this), which is an MFC encapsulation of this AFAIK.
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Just came across this. Very good sample collection on connection string format, just want to share it with u all:
http://www.able-consulting.com/MDAC/ADO/Connection/OLEDB_Providers.htm#OLEDBProviderForSQLServer
And to moderator:
is it possible that u put a similar tutorial on your site? It's very handy and will be very helpful later on.
Thanks.
norm
norm
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I have a background in my CListCtrl. I don't want it to scroll though. How does one stop that from happening? Thanks for any help.
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Repaint the background everytime you do any scroll event, perhaps?
But you'll need to double buffer your painting to prevent flicker I think!
Perhaps not much for help this but anyway...
Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!
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I was wondering if anyone here has had any experience with using Waitable timers.
I am in the process of writing a scheduler, similar to SQL Server's Job scheduling utility. The reason i need it is because SQL server doesn't meet all of my criterias.
Now, I have been reviewing various ways of scheduling jobs and I posted earlier on this topic, except for it got buried under various other posts.
I was wondering whether Waitable Timers or TimerQueues are good candidates for a scheduling device? I guess what I would be doing is create all these timers for every job scheduled and then waitonmultiple objects. And I guess my WaitOnMulitple object parameter must be set to true, to allow things to go through as soon as they are signalled.
So, are there any issues and problems that these two suffer from?
thanks
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I'm ranging through a CEdit object's lines, but every time I do the following, LineLength() returns the length of the first edit line. 
Any help? I understand this function, LineLength(i), to return the length of the edit control line, whose index is zero-based, i. That much is correct, right?
CString sLine;
for(int i=0; i<m_Edit->GetLineCount();i++)
{
m_Edit->GetLine(i, sLine.GetBuffer(m_Edit->LineLength(i)), m_Edit->LineLength(i));
...
...
}
BW
"I'm coming with you! I got you fired, it's the least I can do. Well, the least I could do is absolutely nothing, but I'll go you one better and come along!"
- Homer J. Simpson
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Have you tried the following instead?
CString sLine;
for(int i=0; i<m_edit->GetLineCount();i++)
{
m_Edit->GetLine(i, sLine);
...
...
}
(I would've tried this on my machine -- but I'm building a huge project at the moment..)
"No one goes to hell because of their sin, but because of rejecting God's method of salvation: His Son's life for yours..."
"It does not take a majority to prevail ... but rather an irate, tireless minority, keen on setting brushfires of freedom in the minds of men." --Samuel Adams
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The MSDN says LineLength returns the length of the line which contains the character at index "nLine" (I know, great way to name the parameters MS!). So, to get the length of a specified (actual) line index, we'll use LineIndex in conjunction with LineLength:
m_Edit->GetLine(i, sLine.GetBuffer(m_Edit->LineLength(i)), m_Edit->LineLength(m_Edit->LineIndex( i )));
Chris Richardson
Programmers find all sorts of ingenious ways to screw ourselves over. - Tim Smith
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BTW, this worked for me.
Thanks!
BW
"I'm coming with you! I got you fired, it's the least I can do. Well, the least I could do is absolutely nothing, but I'll go you one better and come along!"
- Homer J. Simpson
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Hello everyone,
I have a question about multithreading and syncing data. I have two threads A and B; A feeds data to a cache in B then waits until B is finished with its cache. Example in Pseudo code:
The Mutexes were taken out for code clarity.
A thread:
{
for (I=0; I < 5; ++I)
B->loadData(i);
B->Wait(); // Now wait for thread B to finish processing data.
...
}
B Thread
{
Handle dwWait;
Handle dwRun;
Vector<int> vI;
ThreadFunc()
{
while (1)
{
WORD wdCheck = WaitForSingleObject(dwRun, INFINITE);
switch (wdCheck)
{
case: 0
{
for (int I = 0; I < vI.size(); ++I)
...
SetEvent(dwWait); // Now vector is empty send event.
}
case: 1
{
}
}
}
void Wait()
{
WaitForSingleObject(dwWait, INFINITE);
}
void loadData(int I)
{
vI.push_back(I);
SetEvent(dwRun);
}
}
My question is, why doesn’t thread A always wait for Thread B to finish before continuing on.
Thanks in advance.
Ken
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The key is in the piece of pseucode:
for (I=0; I < 5; ++I)
B->loadData(i); This feeds the cache with 5 ints, signalling dwRun after inserting each int. So, imagine the following (possible) pattern of execution:- A feeds the 1st
int.
- A sets
dwRun.
- The system yields controls to B.
- B processes the cache (containing only one
int) and sets dwWait.
- The system yields controls to A.
- A loads the remaining four
ints, setting dwRun after each insertion.
- A
Waits and exits immediately, as dwWait is already set. There's still some data in B's cache.
See the problem now?
Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo
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