In SharePoint object model while getting the data from large
lists through SPQuery, we can get SPQueryThrottleException saying that “The
attempted operation is prohibited because it exceeds the list view threshold
enforced by the administrator”. We can get rid of this exception by
using Content Iterator (CI). Content Iterator provides implementation interface
for SharePoint objects to regularize the amount of data to be transferred. This
will helps queries in on the lists to not put the load on database excessively.
It will iterate the content in the list instead of executing the query. So that
it will process each item in the list to avoid the throttling limits.
We can process the content iterator to crawl the list items.
Following is the sample code will give us the detail about Content Iterator
processing
public static void ProcessListItems(SPWeb
site)
{
string iteratorName = "item
iterator";
ContentIterator iterator = new ContentIterator(iteratorName);
iterator.ProcessLists(site.Lists,
delegate(SPList list){
ContentIterator.EnsureFieldIndexed(list,
list.Fields.GetFieldByInternalName("Title").Id);
string query = "<Where><And><BeginsWith><FieldRef
Name='Title' /><Value
Type='Text'></Value>RT</BeginsWith></And></Where>";
ContentIterator itemsIterator = new ContentIterator(iterator);
itemsIterator.ProcessListItems(list,query,true,
delegate(SPListItemCollection
items){
foreach (SPListItem
item in items){
ProcessItem(item);
}
},null);
},
delegate(SPList list, Exception e)
{
OnListException(list, e);
});
}
