How to get only the schema of the database into a dataset?
How to load only the schema of the tables into a dataset. ...
dataset
What does the VisualStudio Dataset visualizer exclaimation mark mean?
Some rows in the dataset visualizer have an exclamation mark for each column, other rows have the data as expected. I have been unable to track down a description for the exclamation mark or indeed any symbol within the dataset visualizer. ...
What is a strongly typed dataset?
What is a strongly typed dataset? (.net) ...
compare data in a vb.net dataset with values in an array list
I'm looking for an efficient way of searching through a dataset to see if an item exists. I have an arraylist of ~6000 items and I need to determine which of those doesn't exist in the dataset by comparing each item within the arraylist with data in a particular column of the dataset. I attempted to loop through each item in the datase...
C# Datasets, paging and large amounts of data.
I want to show a large amount of data in a dataset, 100,000 records approx 10 columns, this consumes a large amount of ram 700MB. I have also tried using paging which reduces this by about 15-20% but I don't really like the Previous/Next buttons involved when using paging. I'm not writing the data to disk at present, should I be? If so w...
Managing Data Prefetching and Dependencies with .NET Typed Datasets
I'm using .NET typed datasets on a project, and I often get into situations where I prefetch data from several tables into a dataset and then pass that dataset to several methods for processing. It seems cleaner to let each method decide exactly which data it needs and then load the data itself. However, several of the methods work with ...
Keeping data in session vs. populate on postback
What is preferable, keeping a dataset in session or filling the dataset on each postback? ...
DataColumns and Captions
I'm trying to set up user-friendly captions in a DataSet which will be detected by an Infragistics grid during the binding process. I seem to recall that it was possible to do this in the underlying XSD of the typed dataset but any relevant links to this seem to have fallen off Google's relevant link list. Has anyone done this, would re...
Delphi: Displaying a subset of a data set in data-aware controls
I've got an in-memory dataset with several fields, one of which is a primary key that another dataset references as a foreign key. Thing is, the master dataset can have multiple references to the detail dataset. (This is modeling an object that contains a dynamic array of other objects.) If there was only one of each sub-object, I cou...
Delphi: using TClientDataset as an in-memory dataset
According to this page, it's possible to use TClientDataset as an in-memory dataset, completely independent of any actual databases or files. It describes how to setup the dataset's table structure and how to load data into it at runtime. But when I tried to follow its instructions in D2009, step 4 (table.Open) raised an exception. It...
Delphi: "Invalid field type" error with master/detail datasets
I asked about setting up an in-memory dataset with TClientDataset, and was told I had to use the "Create Data Set" command in the form designer. That works just fine until I try to create a master-detail database relation. If I have a field def of type ftDataSet, then running the Create Data Set command (or calling the method at runtim...
Using DataAdapter .Update to insert/upd rows in dataset (not based on DBs PK) problem
I have a batch process that reads data from multiple tables into a dataset based on a common key. I then build a second dataset of the destination data querying on the same key. At this point I have two Datasets that are structurally identical (from a table/column layout perspective). I then have a process that adds any row that exis...
Creating a dataset.designer.vb from xsd
I have an xsd, , vb, xsc, and xss file for a dataset in VS 2008 that I copied over from another VS project, however I need to make changes to the dataset. Thus I got into the xsd file, created new columns, deleted ones that aren't needed, etc., etc. However I realized when I attempted to use the new dataset I did not have the vb code b...
Tips for using Visual Studio Typed DataSets?
When using strongly typed dataSets in Visual Studio 2005/2008, if the underlying database schema changes, the only practical way to refresh is to delete the dataset and recreate it from scratch. This is OK unless I need to customize the dataset. Customizing by extending the partial dataset class allows customizations to be retained, b...
Programming pattern using typed datasets in VS 2008
I'm currently doing the following to use typed datasets in vs2008: Right click on "app_code" add new dataset, name it tableDS. Open tableDS, right click, add "table adapter" In the wizard, choose a pre defined connection string, "use SQL statements" select * from tablename and next + next to finish. (I generate one table adapter fo...
Typed DataSet connection - required to have one in the .xsd file?
In the .xsd file for a typed DataSet in .NET, there's a <Connections> section that contains a list of any data connections I've used to set up the DataTables and TableAdapters. There are times when I'd prefer not to have those there. For instance, sometimes I prefer to pass in a connection string to a custom constructor and use that ra...
Problem Implementing XmlTextWriter in new XmlRecordsetWriter for Streams
For background see my question here. So the problem now isn't that I can't send a DataSet to classic ASP but that it can't do anything with it. So I found some code to create a recordset xml structure from a DataSet. I have tweaked it a little from it's original source. The problem is that I can't seem to extract the base stream and ...
Using LINQ to get column value from column name when you have the row?
I'm trying to convert some code that uses datasets to LINQ. Some of the code passes column names into other functions as strings. Is there anyway I can easily rewrite this into LINQ? string s = getElement(tr, elementName); private string getElement (tableRow re, string elementName){ if(tr[elementName] != null){ return tr[...
How do I improve performance of DataSet.ReadXml if I'm using a schema?
I'm have a ADO DataSet that I'm loading from its XML file via ReadXml. The data and the schema are in separate files. Right now, it takes close to 13 seconds to load this DataSet. I can cut this to 700 milliseconds if I don't read the DataSet's schema and just let ReadXml infer the schema, but then the resulting DataSet doesn't contai...
Batch Updates using DataAdapter
I have a situation where I have a bunch of SQL Update commands that all need to be executed. I know that DataSets can do batch updates, but the only way I've been able to accomplish it is to load the whole table into a dataset first. What if I want to only update a subset of the records in a table? ...