accessing a database using visual studio net

... the data in your test database might be real data and must be there when users begin to use the application For example, your database might have a table that contains valid grade values ... use a tool 11 such as SQL Server Management Studio More information about deploying database changes to SQL Server Compact databases is provided in the Deploying a Database Change ... the database engine itself as part of your web application Another advantage is that it's relatively simple to back up and restore your production data because the data is all in an sdf

Ngày tải lên: 20/10/2014, 14:03

... relational database approach for organizing data. Trang 24Chapter Summary (cont.)• Visual Basic NET uses ADO.NET to access and manage databases. • The DataGrid control is a control that can ... related tables. Trang 98.1 A Relational Database Primer (cont.)Trang 108.1 A Relational Database Primer (cont.)• Database Queries – Most relational database systems use a query language called ... Relational Database Primer (cont.)• Relational Database Tables – A relational database stores the data for each entity in a table with rows and columns. – Compatible with Visual Basic NET. – A key

Ngày tải lên: 16/05/2017, 14:41

... idatabase m qua ADO, application trong NET làm vi c v i portabledatabase ch ch a m t hai tables, là copy t database m Khi nào c n,portable database này (ADO.NET) s đ c reconciled v i database ... MyBase.Load Dim ds As New DataSet () ' Instantiate a Dataset ' Instantiate an OleDbDataAdapter for Access2000 database Authors.mdb and return table Authors Dim myData As New OleDbDataAdapter("Select ... các database qua HTTP, ADO và CDO (Collaborative Data Objects), v.v Data Tier: Th ng là relational database nh Microsoft SQL Server hayOracle Ngoài ra còn có Exchange hay các database x a c a mainframe

Ngày tải lên: 25/10/2013, 06:15

... to as a disconnected DataSet as it doesn't maintain an active connection to the database Disconnected DataSet objects act as a data cache in applications You can modify the data in the DataSet, ... time Instead, a better approach is to connect to the database, fetch the data into a DataSet object, and then disconnect again The user can browse the data in the DataSet and make any changes required ... form and return to Visual Studio 2005 Performing Updates by Using a DataSet The changes made by using the DataGridView control are automatically copied back to the DataSet acting as the data source

Ngày tải lên: 15/12/2013, 00:15

... lose answering users’ questions later Part VI; Constants, Arrays, and Variables: This part helps you out with the syntax for declaring constants, arrays, and various variables in Visual C++ Part ... ready-to-run libraries a program can summon at will If you have code that more than one program uses, such as database access, you can build a DLL and load it at run time The wizard does not create source ... falls under, and then look at the alphabetical listings in that part For example, if you want to find out how to declare a pointer in Visual C++, go to the part on Constants, Arrays, and Variables,

Ngày tải lên: 25/03/2014, 16:07

... say that the class has been encapsulated A major benefit of OOP is that because the data and methods encapsulated inclasses are so closely tied together, we do not need to passarguments back and ... expiration is DaysC and the number oftrading days till expiration is DaysT, then DaysT is calculated as Trang 10DaysT ¼DaysC
2  int(DaysC=7) To convert calendar-day volatilities to trading-day ... to an ATM volatility that is, for example, 30 calendar daysout (which is somewhat difficult to envision since only on 1 day a month will an expiration be exactly 30 days away), we need amathematical

Ngày tải lên: 20/06/2014, 23:20

... there are two types of databases used in financial markets: operational databases and analytical databases Operational databases store dynamic data such as portfolio and position information ... information Analytical databases hold static data such as historical price or trade history data, often in a flat file Regardless of the brand of database software, both these types of databases ... systems. As shown in Chapter 8, correlations and covariances are calculated using historical price data. But covariances can also be updated and forecast using GARCH methodologies since covariance rates

Ngày tải lên: 20/06/2014, 23:20

... data in a database as well aschanging the structure of tables within a database.SQL consists of a limited number of SQL statements andkeywords, which can be arranged logically to perform transactionsagainst ... the database, you may need to include a COMMIT If you havemade an error in updating data and wish to restore your privatecopy of the database to the way it was before you started, you may be able ... writing a simple VB.NET program to generate thebar data and save it to a new database Let’s look at some of the common types of bad data we oftenencounter in financial markets: Type of Bad quotes

Ngày tải lên: 20/06/2014, 23:20

... OleDbDataAdapter("Select * From OptionTrades, _ myConnect) Dim myDataSet As New DataSet() myConnect.Open() myAdapter.Fill(myDataSet, "myData") DataGrid1.DataSource = myDataSet DataGrid1.DataMember ... a database into XML. VB.NET DataSet objects provide methods that create XML documents from a data table and that also can convert XML data into a data source. This is accomplished through the ... implementing a form of SAX parser to make sure the XML message is well formed. However, an XmlTextReader object will not perform data validation against a DTD. To perform data validation, we could use an

Ngày tải lên: 20/06/2014, 23:20

... Trang 1Nguyễn Văn Trung Giáo trình thực hành Chuyên đề Lập trình với Visual Studio NET Các ví dụ được minh họa trên môi trường Microsoft Visual Studio 2005 Bài tập thực hành Visual Studio NET ... chọn Ad wse của h đã tạo ra trưthư viện đượ bàn phím, sa Application ư viện commpascalTriang dd Reference hộp thoại ước đó ợc tham khảo au đó in ra m n Đặt tên promonUtils bằngle1 trong cửe… Trang ... theinhVienVan Trang 17p dữ liệu các cao nhất trườnhập danh ) Trang 18Giá Form Hell Style Fixe trị mMain lo WinForms edSingle Application, đ sinh ra Chỉ Gh Ti Kí đổ Vô a sổ a cửa sỗ sẽ kh

Ngày tải lên: 21/06/2014, 09:20

... Trang 1ADO NET With the introduction of ADO NET, data access has become much easier, and Crystal Reports NET can take advantage of ADO and the ADO NET dataset Instead of having to work ... the data source will be a relational database, but the data could also reside in spreadsheets, text files, OLAP (Online Analytical Processing) data structures, and even nonrelational data sources ... needs and the data sources available to you Data Source Description Project Data Crystal Reports NET can leverage the ADO NET Framework and report directly from datasets that appear in your application

Ngày tải lên: 06/08/2014, 09:20

... Reports NET can leverage the ADO NET Framework and report directly from datasets that appear in your application For more information on how Crystal Reports NET can be used with ADO NET data, please ... structures are similar to Visual Basic, which many developers are familiar with, and it is easy for developers to create formulas using a language that is familiar to them Which language you use ... select Database → Add/Remove Database to open the Database Expert shown in Figure 3-2 There are a number of different types of data sources available, and though these were covered in Chapter

Ngày tải lên: 06/08/2014, 09:20

... chapter, you will be able to actually look at the application we are creating and other examples that illustrate points along the way Planning Your Application Integrating reports is an easy ... back from the database Creating a Parameter Field The first step in creating a parameter field is specifying a name for that field Once you have created your parameter field, Crystal Reports will ... name in curly brackets, preceded by a ques­tion mark to indicate it is a parameter field ({?ParamFieldName}) You can also enter prompting text that will appear whenever the Parameter Field dialog

Ngày tải lên: 06/08/2014, 09:20

... using an Access database and it had been moved and was no longer available, you could set the UserData property to a string containing the location to the UserData, and that particular database ... in Chapter 8, “Formulas and Logic.” Refreshing the Data in a Report When a report is refreshed, it goes back to the database for the most current set of data available and runs again Drag and ... performance; if your database is only updated once a day (or once a month), you can keep track of how many times a user attempts to hit the database, and simply remind users with an information

Ngày tải lên: 06/08/2014, 09:20

... ParameterField() Dim myDiscreteValue As New ParameterDiscreteValue() Dim myRangeValues as New ParameterRangeValues() myParameterField = New ParameterField() myParameterField.ParameterFieldName ... myParameterField.ParameterFieldName = “LastYearsSales” myRangeValues.StartValue = 100000 myRangeValues.EndValue = 500000 myParameterField.CurrentValues.Add(myRangeValue) myParameterFields.Add(myParameterField) You can also combine ... this parameter Because in this example we are passing only a discrete value to the parameter, we would simply create a variable by dimensioning it as a ParameterDiscreteValue All we need to do at

Ngày tải lên: 06/08/2014, 09:20