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Scott. Gus Blog Building a DAL using Strongly Typed Table. Adapters and Data. AdoDotNetDbAccess.gif' alt='Tableadapter Update' title='Tableadapter Update' />Tableadapter Visual BasicVb Net Access DbTables in VS 2. ASP. NET 2. 0. June 2. Update Weve now published a whole series of new data tutorials based on this origional post. You can read all about it here. One of my goals over the next few weeks is to publish a number of quick tutorial postings that walkthrough implementing common data binding design patterns using ASP. Save data with the TableAdapter DBDirect methods. Update method that performs. Add methods to directly access the database and. NET 2. 0 master details, filtering, sorting, paging, 2 way data binding, editing, insertion, deletion, hierarchical data browsing, hierarchical drill down, optimistic concurrency, etc, etc. To help keep these samples shorter, and to help link them together, Im going to use a common DAL data access layer implementation across the samples that is based on SQL Servers Northwind sample database. To build the DAL layer I decided to use the new Data. Set Designer that is built into Visual Web Developer which you can download for free as well as VS 2. TableAdapter queries are SQL statements or. TableAdapter queries can. Directly Access the Database with a TableAdapter. Ive used it for a few samples lately, and have found it pretty useful and flexible. I really like the fact that it enables me to avoid having to write tedious data access code, while still preserving full control over my SQL data logic I also like the fact that it enables me to use both standard SQL statements as well as SPROCs. One of the things that Ive noticed is that there arent a lot of end to end tutorials that show off how to build and use a DAL with the designer one exception is the great write up by Brian Noyes who includes samples of how to use it with SPROCs. What Ive tried to do with the below set of tutorials is provide an end to end, step by step, walkthrough that covers all of the core concepts involved in creating and consuming a DAL built with the data designer. Using the data designer and ASP. NET 2. 0 together, you should be able to create a core DAL implementation and build from scratch a data driven UI web app on top of an existing database very quickly 1. The final result of the below walkthroughs can be downloaded here. This download includes all of the code samples as well as the DAL built up below. Ill then be posting lots of much shorterUI patterns that use it. Tutorial 1 Creating a Web Project and Connecting To the Database. To begin with, create an empty new ASP. NET Web Site Project File New Web Site within Visual Web Developer. We can then connect and load our Northwinds database in the IDE. To do this you can follow one of two approaches Option 1 Connect to a local or remote SQL 2. SQL 2. 00. 5 database that has the Northwinds sample installed. To do this, go to the Server Explorer property window in Visual Web Developer choose View Server Explorer if it isnt currently visible, right click on the Data Connections node and choose to add a new database connection. You can then walkthrough a wizard to pick your SQL database and load the Northwinds database in the IDE Option 2 If you dont have a SQL 2. SQL 2. 00. 5, you can alternatively use the free SQL 2. Express Edition.   Download this. Northwinds. mdf database file, and copy it to the AppData directory underneath your web sites root directory. Click the Refresh button in the solution explorer, and it will appear in the Solution Explorer SQL Express databases within the AppData directory will automatically show up as a listed item in the Server Explorer property window note I sometimes get a timeout error the very first time I expand a newly copied sql express database here I think because it is generating the log file the first time it is accessed. If this happens just click it again and it seems to immediately expands After the Northwinds database has been loaded using either Option 1 or Option 2 above, you can expand, view, edit, and add to any of the tables, stored procedures, views, triggers, etc with the database. You can also use the query builder to test out and run queries against the database or right click on a table and choose Show Table Data to see all of it. Tutorial 2 Launching the Data. Set Designer. To create our Northwind DAL, right click on the project node in the solution explorer, and select Add New Item. Then select the Data. Set option and name it Northwind. Using+Typed+DataSets+and+TableAdapters.jpg' alt='Tableadapter Tutorial' title='Tableadapter Tutorial' />This will prompt me as to whether I want to add it under the AppCode directory. When I click yes it will bring up a data design surface, and if in a web project automatically launch the Create Table. Adapter wizard if you are in a class library project you need to right click and choose Add Table Adapter to launch this wizard Tutorial 3 Creating our First Table Adapter. The Create Table. Adapter wizard will first prompt me for the database to use, and provide a list of all database connections currently registered in Visual Web Developers server explorer window note you can also create new connections from this wizard if you want. After I choose the Northwind database I want to use, it will prompt me for where to store the database connection string. By default it will avoid hard coding it within your code, and will instead save it within the new lt connection. Strings section of your web. Class Library Project. Note that with. NET 2. ASP. NET 2. 0 Property Page within the IIS GUI Admin Tool to change it later ideal for administrators. Pick a name for what you want to call it You can then choose how you want to configure the Table. Adapter you can use either SQL Statements that you embed within your DAL layer, or stored procedures SPROCs that you call from it For our first table adapter well use a SQL Statement. You can either type this in directly within the next window Or alternatively launch the query builder from that wizard step to graphically construct it one handy feature with it is the ability to execute test queries to validate results Once weve finished building and testing our query, we will return back to the Enter a SQL Statement page. Before moving to the next page, well want to click the Advanced Options button to verify what type of operations we want the designer to generate The above dialog shows the default settings that are set when you run the Create Table. Adapter wizard from within a VS 2. Web Site Project these are the most common data patterns we typically see developers use with stateless web applications. When you run the wizard from within a Class Library Project or from a Windows Client Project, the Use Optimistic Concurrency checkbox will be selected by default as well. For the purposes of this DAL walkthrough, we want to turn off optimistic concurrency note one of my later blog postings on optimistic concurrency will change that setting but I will be showing straight updates first. When we click next on the wizard again, well be prompted for the method names we want to create in our DAL to run our Category SQL query. There are two patterns of data usage that this data wizard can generate one is the Fill pattern used with Data. Ghostscript Convert Pdf To Tiff Command Line. Sets, that will generate a method that accepts a Data. Set or Data. Table parameter that we want to add category information to. The second pattern of data usage is one where we will generate a method that will simply return a new Data. C Table. Adapter Insert Method Missing. Table. Adapter Generate. Db. Direct. Methods. Tableadapter Update Not Working' title='Tableadapter Update Not Working' />In addition to the Insert. Command, Update. Command, and Delete. Command, Table. Adapters are created with methods that can be executed directly against the database. These methods Table. Adapter. Insert, Table. Adapter. Update, and Table. Adapter. Delete can be called directly to manipulate data in the database. If you do not want to create these direct methods, set the Table. Adapters Generate. Db. Direct. Methods property to false in the Properties window. Additional queries added to the Table. Adapter are standalone queries they do not generate these methods. Youll find this option at the designer in the second last page. Create methods to send updates directly to the database. Note This is not the same then clicking Advanced Options and click Generate Insert, Update, and Delete statements. When you select this option, the wizard will attempt to generate INSERT, UPDATE, and DELETE statements based on the SELECT statement defined on the Generate SQL statements page. Edit The Table. Adapter cannot create insert,update and delete statements automatically when more than one table is involved in the main select query. There are several approaches if you need one or more columns of related tables, the best way depends on your requirement. Add insert,update and delete queries manually to the Table. Adapter. These methods can be called directly from an instance of the Table. Adapterf. e. Insert. Userparam. 1,param. Add insert,update and delete commands manually to the Table. Adapterdesigner or programmatically. These commands will be triggered implicitely from the Table. Adapter when you call Update. The Data. Rows Row. State determines which command will be triggeredf. Added Insert. Command. Select one table and join the tables via relations to other tables in the Data. Set. For the third approach you could use LINQ To Data. Set to join the related tables to get all needed columnsf. Data. Source for a Grid.