public class SortingDegrader extends Searcher
Queries are eligible if they do sorting, don't do grouping, and the first sort criteria is a fast-search attribute.
Modifier and Type | Field and Description |
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static com.yahoo.processing.request.CompoundName |
DEGRADING
Set this to false in query.properties to turn off degrading.
|
static com.yahoo.processing.request.CompoundName |
PAGINATION |
Constructor and Description |
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SortingDegrader() |
Modifier and Type | Method and Description |
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private long |
decideDefaultMaxHits(Query query)
Look at a "reasonable" number of this by default.
|
Result |
search(Query query,
Execution execution)
Override this to implement your searcher.
|
private void |
setDegradation(Query query) |
private boolean |
shouldBeDegraded(Query query,
IndexFacts.Session indexFacts) |
ensureFilled, fill, getLogger, process, toString
getAnnotatedDependencies, getDefaultAnnotatedDependencies, getDependencies, initDependencies
public static final com.yahoo.processing.request.CompoundName DEGRADING
public static final com.yahoo.processing.request.CompoundName PAGINATION
public Result search(Query query, Execution execution)
Searcher
Searcher implementation subclasses will, depending on their type of logic, do one of the following:
Hits come in two kinds - concrete hits are actual content of the kind requested by the user, meta hits are hits which provides information about the collection of hits, on the query, the service and so on.
The query specifies a window into a larger result list that must be returned from the searcher through hits and offset; Searchers which returns list of hits in the top level in the result must return at least hits number of hits (or if impossible; all that are available), starting at the given offset. In addition, searchers are allowed to return any number of meta hits (although this number is expected to be low). For hits contained in nested hit groups, the concept of a window defined by hits and offset is not well defined and does not apply.
Error handling in searchers:
private boolean shouldBeDegraded(Query query, IndexFacts.Session indexFacts)
private void setDegradation(Query query)
private long decideDefaultMaxHits(Query query)
If maxhits/offset is set high, use that as the default instead because it means somebody will want to be able to get lots of hits. We could use hits+offset instead of maxhits+maxoffset but that would destroy pagination with large values because totalHits is wrong.
If we ever get around to estimate totalhits we can rethink this.
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