Delphi: using TClientDataset as an in-memory dataset

delphi dataset
Mason Wheeler picture Mason Wheeler · Nov 8, 2008 · Viewed 63.2k times · Source

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 said that it didn't have a provider specified.

The entire point of the example on that page is to build a dataset that doesn't need a provider. Is the page wrong, is it outdated, or am I missing a step somewhere? And if the page is wrong, what do I need to use instead to create a completely independent in-memory dataset? I've been using TJvMemoryData, but if possible I'd like to reduce the amount of extra dependencies that my dataset adds into my project.

Answer

MikeJ picture MikeJ · Nov 8, 2008

At runtime you can use table.CreateDataset or if this is on a design surface you can right click on the CDS and click create dataset. You need to have specified columns/types for the CDS before you can do this though.

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