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A Foundset may be automatically updated when the client receives a Data Broadcast Event . If the data change affected the table to which the foundset is bound, the foundset will be refreshed to reflect the change.
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Performing Batch UpdatesFoundsets are typically updated on a record-by-record basis, either as the user operates on a foundset-bound GUI component, or through programmatic interactions. However, sometimes it is necessary to perform an update to an entire foundset. For performance reasons, it is not advised that this be done by programmatically iterating over the foundset's records. Rather, it is recommended that batch updates be performed using the JSFoundsetUpdater API. The Foundset Updater API is ideal to use for the following situations: Updating an Entire FoundsetThis essentially has the effect of issuing a SQL UPDATE statement using the WHERE clause that constrains the foundset. This presents a significant performance advantage over updating records individually. In the example below, a related foundset is updated, meaning all orders belonging to the selected customer will be affected.
Updating a Partial Foundset with Different Values for Each RecordThe Foundset Updater API can also be used to update part of a foundset. Moreover, unlike the above example, this approach allows for different values for each record. In the example below, the first 4 records (starting from the selected index) are updated by specifying an array of values for each column that is affected.
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The Foundset Updater API can also be used to update records individually, but still holds a performance advantage over iterating on a foundset, which has more overhead and can cause the foundset's cache size to increase unnecessarily. In the example below, each record in the foundset is updated with a unique value (A simple counter is incremented, which is arbitrary, but demonstrates that each record can be updated with a unique value.)
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var count = 0;
var fsUpdater = databaseManager.getFoundSetUpdater(foundset)
while(fsUpdater.next())
{
fsUpdater.setColumn('degrees',count++);
}
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When
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