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Himalay,
IMO, Datasets are better to bind to a gridview. Assuming you are using SQL 2000/2005 (you didn't specify which database you are using), 200 users at the same time and 25 records in each dataset, you should not have much in concern of performance.
I think your question is a matter of preference.
Paul
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I create a form with a dataset (Fill from 3 dataadpater ).
My form work ok , and have a textbox and datagrid with a relation to my records in textbox.
I create a dataview to filter the records.
After that the textbox don´t change.
I have this code, and it don't work
editNome.DataBindings.Add(New Binding("Text", DsFunc, "TFuncionarios.Nome"))
I try this code , and my textbox show de result.
editNome.DataBindings.Clear()
editNome.DataBindings.Add(New Binding("Text", DsFunc.Tables("TFuncionarios"), "Nome"))
-----------------------------------
Private Sub btnNext_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSeguinte.Click
If Me.BindingContext(DsFunc.Tables("TFuncionarios")).Position < DsFunc.Tables("TFuncionarios").Rows.Count - 1 Then
Me.BindingContext(DsFunc.Tables("TFuncionarios")).Position += 1
End If
but another thing appens the data grid don't move when i go to next record.
i think is something with the databinding.
What i must do to make textbox related with my datagrid ???
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Hai
I am using SQl Server 2005 BETA 2. When i try to import data from an Access, into one of my DB using Server Mangement Studio(Right Clicking DB and Select Import Menu Item) . The Import Fails with an error
Error 0xc02020f6: Data Flow Task: Column "Description" cannot convert between unicode and non-unicode string data types.
(SQL Server Import and Export Wizard)
How can i solve this problem.
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I'm an SQL nebie, so bear with me:
I need to collect the following data after parsing a bunch of c/c++ files and then storing the parsed data as a serious of records that store the symbol type (is it a function class/struct/union, variable, enum etc), the symbol name, offset, and a few other values.
I would like to enter this data into one or more tables for easy searching later on.
My question is: is it better to design multiple tables, for example one table for classes/structs/unions, another table for functions, another for variables/member vars, and a fourth for miscellaneous stuff, or one single table? I would prefer whatever results in a faster return of the results.
If I have multiple tables, what is the proper way to glob all the results (from selecting across multiple tables) into one result set?
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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My initial reaction is that this would best be in several tables.
I would create a small symbol_types table with an identity field as primary key, and a unique index on the symbol_type field (NVarChar)
similarly a Files table with the file path and an ID (identity) field.
The main table would contain symbol_name, TypeID (ID from symbol_types), PathID ( ID from files) and the rest of the story (but look for other opportunities to segregate repeated string data into a lookup table like "symbol_types"). This table should likely have a compound primary key on Symbol_name,TypeId and PathID to allow for multiple occurences of the same symbol_name (either that or an identity field for primary key, and just a unique index on the previously mentioned three fields). The idea here is to consolidate repeated strings into a single table so they can be represented by the integer key for the row that contains the one instance of the string. This makes it much easier and less expensive to update a symbol type name (to correct spelling for instance), and reduces the record size in the main table by replacing the repeated strings with an integer value. This makes for much faster selection queries, since extracting groups of records from the main table ( all symbols of a certain type, for instance) a match on integer id's rather than a string comparison) - "Select [symbol name] from [symbol table] inner join [symbol types] on [symbol name].[TypeID] = [symbol types].id where [symbol types].[typename] = 'member'").
The proper way to "glob them all together" is to use an inner join query " select [S.symbol name], [T.Typename],[P.Path]...from [symbol table] as S inner join [symbol_types] as T on S.TypId = T.ID inner join Files as P on s.Pathid = P.ID" (warning: syntax may not be quite correct, check documentation for your database on proper way to make inner join). Note that you often cannot directy update the database using the resulting recordset, but must instead update the underlying base tables one by one.
Absolute faith corrupts as absolutely as absolute power
Eric Hoffer
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke
-- modified at 23:15 Monday 23rd January, 2006
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Wow! Thanks for the info. I appreciate the detailed response, since I don't know that much about SQL!
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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Well I tried this technique with SQLite. And got all the data entered, my main symbols table had over 11,000 entries, and the functions table over 7200. And getting things to join takes FOREVER (about 20 secs)!!! It's insanely slow (this on a P4 3 GHz with HT). So while I much prefer the organization of this method, it seems like it just isn't going to work well with sqlite. I suspect that this is a problem with sqlite.
Just for kicks here's how I created the tables:
CREATE TABLE Types (
TypeID INTEGER PRIMARY KEY
, TypeInfo CHAR(125)
);
CREATE TABLE Templates (
TemplateID INTEGER PRIMARY KEY
, TemplateSignature CHAR(125)
);
CREATE TABLE Files (
FileID INTEGER PRIMARY KEY
, Path CHAR(255)
);
CREATE TABLE Symbols (
Id INTEGER PRIMARY KEY
, Kind INTEGER
, Name CHAR(125)
, FileID INTEGER
, TypeID INTEGER
, Offset INTEGER
, LineNumber INTEGER
, TemplateID INTEGER DEFAULT 0 NOT NULL
, Parent INTEGER DEFAULT 0
);
CREATE TABLE Functions (
FuncID INTEGER PRIMARY KEY
, Signature CHAR(125)
, SymbolID INTEGER
, ReturnTypeID INTEGER NOT NULL
);
I left out the FK stuff as sqlite ignores it apparently.
For the query I tried:
select symbols.name,functions.signature from symbols, functions where
functions.symbolid = symbols.id;
It does eventually return, but it's impossible to use, so for now I think I'm just going to go with the single table approach. The query is a little more difficult to formulate, but it's *really* fast.
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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Well it apepars I spoke too soon. The problem was that I didn't have an index built for the functions.sybolid column. Once I did that the query completed instaneously! Woot!
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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If your use cases are such that at most of the places you need to lookup objects of one particular type (e.g., give me a class by this name, give me all the variables with this property, ...), you may be better off storing objects of each type in a separate table. This will help in better performance because less number of records needs to be filtered during a query for a particular type of object. This will also provide better data normalization if the information for each type is quite different than that for the other ones.
If you are developing your application in C# or some other managed language, you may use an OR-Mapping product to totally avoid dealing with tedious low-level infrastructire code in ADO.NET or OleDb for data integration. For example, with NJDX OR-Mapper, you may do the following:
1- Define your domain model classes (say AClass, AStruct, AUnion, AVariable, AnEnum, etc.) with properties for name, offset, etc.). For example,
class AClass {<br />
string name;<br />
int offset;<br />
...<br />
}
If some classes are very similar, you may define them in a class-hierarchy.
2- Define OR-Mapping declaratively like:
CLASS AClass TABLE CLASSES<br />
PRIMARY_KEY name<br />
;<br />
<br />
CLASS AUnion TABLE UNIONS<br />
PRIMARY_KEY name<br />
;
3- Create the database schema using NJDXSchema tool. This will create tables CLASSES, UNIONS, etc, with proper columns and primary keys.
4- Write your application using NJDX APIs. For example, the following code will insert a new object c1 of type AClass in the database:
njdx.insert(c1, 0, null);
The following code will fetch an AUnion object having name="someUnion"
Object oid = ObjectId.createObjectId("AUnion;name=someUnion");<br />
AUnion myUnion = njdx.getObjectById(oid, true, 0, null);
The following code will fetch all AClass objects into the myClasses variable.
ArrayList myClasses = njdx.query("AClass", null, -1, 0, null);
If you have defined some of your classes in a hierarchy, you can fetch all the qualifying objects of all the classes in that hierarchy with one query call.
Essentially, your code will be more object-oriented and easier to evolve. And you will avoid all the complexities of SQL.
Damodar Periwal
Software Tree, Inc.
Simplify Data Integration
http://www.softwaretree.com
-- modified at 18:55 Tuesday 24th January, 2006
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The database is intended to hold a standard description of potententially 10s of thousands of class types. It's going to be populated after scanning a directory (and potentially sub directories) and parsing all the c/c++ files there. So creating a table per class might get a little unwieldy.
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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I did not mean creating one table per end-user class. In my example, the CLASSES table will hold information for all the instances of the AClass class. So essentially, you would be dealing with only a handful of tables - one for all the end-user classes, one for all the end-user structs, one for all the end-user unions, etc.
Damodar Periwal
Software Tree, Inc.
Simplify Data Integration
http://www.softwaretree.com
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Hi,
I need to implement a function that sends emails on a perticular date and time. The date and time is specified by the user when he posts a new event into a on-line calendar. The user should be allowed to decide when an event notification email will be sent to a group of people.
The database used for the project is SQL server. I learn about SQL server job scheduler can do it. But I don't know how to add a job into SQL server job list when a record is submited into database from web form.
Is there anybody having any advices?
Thanks in advance!
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firstly add the time and date from web form to database table for each user.
then add only one job that run after each minute in Management-->SQL Jobs.
Now what this job will be done ?.
It will first check the date and time of users and then it will send mail using following code if the user is reach to its exact time.
Code you can view from following link:
http://www.vbforums.com/archive/index.php/t-280616.html
and read about how to add a new SQL server job in database in detail.
Qaisar Mehmood Mughal
...............................................................................
May Allah gave u success in all fields of life. (Aameen)
...............................................................................
Software Engineer
ISF - Islamabad Software Factory
3rd Floor, Software Technology Park
Constitution Avenue, Islamabad 44000, Pakistan
www.isf.com.pk
qaisar@isf.com.pk , qmmughal@gmail.com
Phone: +92 (51) 2825387 : 0321-5226623
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Thank you very much, Qaisar!
It definitely will help a lot.
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Hello everyone,
I have a rather large query that returns some fields, including a date field. Some dates are in the future, some are in the past, and some of the results are null. I need to find a way to arrange them so the nearest dates to today are displayed, then the ones further away, then the older ones, then the nulls.
Example: given that getDate() = Jan 23 2006 2:41PM
------------
1 Jan 30 2006 3:00PM
2 Jan 20 2006 1:14PM
3 NULL
4 Dec 31 2006 11:00AM
5 Jan 24 2006 7:00PM
6 NULL
I want the result set to be arranged like so:
-----------
1 Jan 24 2006 7:00PM
2 Jan 30 2006 3:00PM
3 Jan 20 2006 1:14PM
4 Dec 31 2006 11:00AM
5 NULL
6 NULL
As perviously mentioned the query is huge so I'd like to avoid using a union if at all possible, just to reduce clutter. But if it needs to be done, it needs to be done.
Any ideas? Thanks in advance!
-------------------
abort, retry, fail?
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jszpila wrote: As perviously mentioned the query is huge so I'd like to avoid using a union if at all possible, just to reduce clutter
Yes, it can be done without UNIONs
SELECT dateColumn,
ABS(DATEDIFF(minute, dateColumn, @distanceFromThisTime)) AS TimeDifference,
CASE WHEN dateColumn IS NULL THEN 0 ELSE 1 END AS Nothing
FROM myTable
ORDER BY CASE WHEN dateColumn IS NULL THEN 0 ELSE 1 END DESC,
ABS(DATEDIFF(minute, dateColumn, @distanceFromThisTime)) ASC
In the above code:
dateColumn is the column that contains the date information.
@distanceFromThisTime is a datetime variable that contains the time that the query is centred on, probably getdate() from your description.
The ORDER BY clause first of all sinks the NULL s to the bottom, then it orders the remaining stuff in ascending order.
Finally, you can obviously ditch the TimeDifference and Nothing columns, I put them in to illustrate what values might be returned if you wanted to try this code in query analyzer first.
Does this help?
ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
-- modified at 17:48 Monday 23rd January, 2006
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Thanks! It's definitely a step in the right direction, but it's kinda goofing the order of the dates. It has successfully pushed all the nulls to the bottom, though.
My results along these lines (I'm doing some formatting in the SQL - I'm doing the formatting independently with an alias so I don't think it would be messing it up):
01/26/06
01/18/06
01/31/06
01/13/06
02/10/06
12/31/05
Seems kinda random. I've tried tweaking and nothing really affects the results coming out that way.
Any other ideas? Thanks again!
-------------------
abort, retry, fail?
-- modified at 18:25 Monday 23rd January, 2006
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jszpila wrote: My results along these lines (I'm doing some formatting in the SQL - I'm doing the formatting independently with an alias so I don't think it would be messing it up):
01/26/06
01/18/06
01/31/06
01/13/06
02/10/06
12/31/05
Assuming you are doing a differential from today 23-Jan-2006
01/26/06 - 3 days from today
01/18/06 - 5 days
01/31/06 - 8 days
01/13/06 - 10 days
02/10/06 - 18 days
12/31/05 - 23 days
Seems reasonable to me. That's why I put the extra columns in the demonstration code, because it does seem a bit random.
ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
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Ah, alright, that makes sense now. I didn't pick up on that right away.
Thanks a ton!
-------------------
abort, retry, fail?
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I have a stored procedure that updates data in one table and saves who updated it and the update date in another table. For some reason, the user ID is updating, but the date isn't. I'm using the GetDate() function, so it should work fine, as far as I know. It's like the update statement doesn't even recognize the second column.
Before you ask, I know the SQL is correct. In fact, if I execute the stored procedure from QA, everything works fine. Are there any issues with using the GetDate() function in a stored procedure? I wouldn't think there are.
Here's my SQL:
UPDATE UserDefinedRows
SET UpdatedByUserId = @UserID,
UpdateDate = GETDATE()
WHERE UserDefinedRowID = @UserDefinedRowID
Michael Flanakin
Web Log
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Oh, and when the SP gets run from the application, it gets run by a DBO user.
Michael Flanakin
Web Log
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I just logged into QA as the user the application is running as and the SP executed fine. I'm still having problems when executing it from the app, tho. This is pretty ridiculous.
Michael Flanakin
Web Log
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UpdateDate = GETDATE()
please past the error message
hint,
if UpdateDate is datatime then it will work properly.
Qaisar Mehmood Mughal
...............................................................................
May Allah gave u success in all fields of life. (Aameen)
...............................................................................
Software Engineer
ISF - Islamabad Software Factory
3rd Floor, Software Technology Park
Constitution Avenue, Islamabad 44000, Pakistan
www.isf.com.pk
qaisar@isf.com.pk , qmmughal@gmail.com
Phone: +92 (51) 2825387 : 0321-5226623
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how to delete a record from the databaseb using ado
yamuna
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yamunasenthilvel wrote: how to delete a record from the databaseb using ado
The simplest way to delete values from a database is.
CString sql = "DELETE * FROM tbl_Name WHERE col =’value’"
pConnection.Execute(sql.AllocSysString(), NULL, adExecuteNoRecords);
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