Preload View
The Preload View property is used to retrieve the entire data view in advance.
If Yes is selected, the runtime engine loads the data of all the records in the task data view.
If No is selected, the runtime engine only loads the first set of records.
If an expression is used, the expression will be computed prior to fetching the records (after the Task Prefix). Therefore, if the expression is based on a local variable that is updated in the Task Prefix, then the Preload view will take the new value into account. (Since version: 1.5)
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When this value is evaluated to TRUE, Magic xpa will fetch all the records in the data view. Therefore, it is not advisable to use this option for large tables.
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This property is enabled only when the Cache Strategy property is set to Position and Data or As Main Source.
When performing a View Refresh, the table is preloaded anew, so if an expression was used in this property, it will be reevaluated.
When the Preload View of the task is set to Yes, the Node Preload property for the Tree control is also regarded as set to Yes.
As a side effect, when the Preload View property is set to Yes, it causes the scroll bar thumb to be recalculated. The scroll bar thumb reflects the size of the table content according to the number of records that are fetched while the task is running. When opening a task, the table reads the first set of records and the thumb size is based on that first set. Then, as the end user scrolls through the records, the thumb is progressively updated.
For the scroll bar to properly indicate the number of records, these records must be preloaded.
The table thumb always reflects the total number of records. As records are added or deleted, the size of the thumb will decrease or increase.
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In Rich Client programs, the data is preloaded to the server and is not sent to the client (Since version: 1.9). Since the Scroll Bar Thumbs are shown according to the data on the client side, the Scroll Bar Thumbs will not be affected by this flag. However, if you use Preload View = Yes and increase the Chunk Size, then the data will be sent to the client, resulting in an accurate thumb.
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Relevant interfaces: Disabled in non-interactive Rich Client tasks
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