Using a TClientDataset, I made a simple set of fields and added some data to it. Then I saved the dataset to the XML format supported by the TClientDataset. Here is the XML: In the ROW nodes, what is the RowState attribute and what are its possible values? In the Params node, what is the Change_Log attribute and what are its possible values? Is there a specification somewhare that describes the XML format used by the TClientDataset? I don't know the specific XML format. But I recently used an XML file to save info from ClientDataSet and this file grew and grew in size. As I found out it stores every change you make in the dataset. Same as it does until you call Applyupdates against a database. But when you store this to file you need to call MergeChangeLog to get the same effect. When you do this before save you get no or Rowstate as this is only information needed to save changes in the dataset. Hopes it helps a little. Per Thomas Brekken. Quote 'Dennis Page' wrote in message news:3a2eac11$1_2@dnews. > Using a TClientDataset, I made a simple set of fields and added some data to > it. Then I saved the dataset to the XML format supported by the > TClientDataset. Here is the XML: > > > > > > > > > > > > > > > > > > In the ROW nodes, what is the RowState attribute and what are its possible > values? > In the Params node, what is the Change_Log attribute and what are its > possible values? > Is there a specification somewhare that describes the XML format used by the > TClientDataset? ![]() Client Dataset Indexes So far, we haven't created any indexes on the client dataset and youmight be wondering if (and why) they're even necessary when sequentialsearches through the dataset (using Locate) are so fast. Indexes are used on client datasets for at least three reasons: • To provide faster access to data. A single Locate operationexecutes very quickly, but if you need to perform thousands of Locateoperations, there is a noticeable performance gain when using indexes. • To enable the client dataset to be sorted on-the-fly. This is useful whenyou want to order the data in a data-aware grid, for example. • To implement maintained aggregates. Load data from flat file. 4 Unload data to flat file. 5.Schedule and execute DB tasks. OraCmd is a command-line tools working with Oracle directly through TCP/IP protocol and doesn't require Oracle client software. ![]() Windows xp live cd mini iso bag 3. The Navigate application demonstrates various navigational techniques. Creating Indexes Like field definitions, indexes can be created at design-time or at runtime.Unlike field definitions, which are usually created at design-time, you mightwant to create and destroy indexes at runtime. For example, some indexes areonly used for a short timesay, to create a report in a certain order. Inthis case, you might want to create the index, use it, and then destroy it. Ifyou constantly need an index, it's better to create it at design-time (orto create it the first time you need it and not destroy it afterward). Creating Indexes at Design-Time To create an index at design-time, click the TClientDataSetcomponent located on the form or data module. In the Object Inspector,double-click the IndexDefs property. The index editor appears. To add an index to the client dataset, right-click the index editor andselect Add from the pop-up menu. Alternately, you can click the Add icon on thetoolbar, or simply press Ins. Next, go back to the Object Inspector and set the appropriate properties forthe index. Table 3.2 shows the index properties. Table 3.2 Index Properties Property Description Name -The name of the index. I recommend prefixing index names with the letters by(as in byName, byState, and so on). Fields -Semicolon-delimited list of fields that make up the index. Example: 'ID' or 'Name;Salary'. DescFields -A list of the fields contained in the Fields property that shouldbe indexed in descending order. For example, to sort ascending by name, and thendescending by salary, set Fields to 'Name;Salary'and DescFields to 'Salary'. CaseInsFields -A list of the fields contained in the Fields property that shouldbe indexed in a manner which is not case sensitive. For example, if the index ison the last and first name, and neither is case sensitive, set Fieldsto 'Last;First' and CaseInsFields to 'Last;First'. GroupingLevel Used for aggregation. Options -Sets additional options on the index.
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