Revision: 7791
http://bigdata.svn.sourceforge.net/bigdata/?rev=7791&view=rev
Author: thompsonbry
Date: 2014-01-14 12:55:58 +0000 (Tue, 14 Jan 2014)
Log Message:
-----------
Added isUnderflow() method.
Modified Paths:
--------------
branches/BIGDATA_RELEASE_1_3_0/bigdata/src/java/com/bigdata/bop/joinGraph/rto/SampleBase.java
Modified: branches/BIGDATA_RELEASE_1_3_0/bigdata/src/java/com/bigdata/bop/joinGraph/rto/SampleBase.java
===================================================================
--- branches/BIGDATA_RELEASE_1_3_0/bigdata/src/java/com/bigdata/bop/joinGraph/rto/SampleBase.java 2014-01-14 12:55:11 UTC (rev 7790)
+++ branches/BIGDATA_RELEASE_1_3_0/bigdata/src/java/com/bigdata/bop/joinGraph/rto/SampleBase.java 2014-01-14 12:55:58 UTC (rev 7791)
@@ -100,6 +100,20 @@
}
/**
+ * Return <code>true</code> iff this sample has cardinality underflow (the
+ * sample is empty). Cardinality underflow occurs when the sampling process
+ * was unable to find any solutions. Underflow is typically addressed by
+ * increasing the sample size, but sometimes underflow indicates that an
+ * access path (if it has filters) or a join may not have any solutions in
+ * the data.
+ */
+ public boolean isUnderflow() {
+
+ return estimateEnum == EstimateEnum.Underflow;
+
+ }
+
+ /**
* Sample.
*/
private final AtomicReference<IBindingSet[]> sampleRef = new AtomicReference<IBindingSet[]>();
This was sent by the SourceForge.net collaborative development platform, the world's largest Open Source development site.
|
