SOLR-11641: Change to default to so default behavior is to PostFilter if user specifies

solr/CHANGES.txt

@@ -120,6 +120,9 @@ Optimizations
 * SOLR-11320: Lock autoscaling triggers when changes they requested are being made. This helps to
   ensure that cluster is in a stable state before processing any new trigger events. (ab)
 
+* SOLR-11641: Change `frange` to default to `cost=100` so default behavior is to PostFilter if user specifies
+  `cache=false` (hossman)
+
 Other Changes
 ----------------------
 * SOLR-11478: Solr should remove itself from live_nodes in zk immediately on shutdown. (Cao Manh Dat)

solr/core/src/java/org/apache/solr/search/FunctionRangeQuery.java

@@ -33,6 +33,7 @@ public class FunctionRangeQuery extends SolrConstantScoreQuery implements PostFi
   public FunctionRangeQuery(ValueSourceRangeFilter filter) {
     super(filter);
     this.rangeFilt = filter;
+    this.cost = 100; // default behavior should be PostFiltering
   }
 
   @Override

solr/core/src/test/org/apache/solr/core/SOLR749Test.java

@@ -83,6 +83,25 @@ public class SOLR749Test extends SolrTestCaseJ4 {
       int count = CountUsageValueSourceParser.getAndClearCount("frange_in_bq");
       assertTrue("frange_in_bq: " + count, (19 <= count && count <= 20));
 
+      // non-cached frange queries should default to post-filtering
+      // (ie: only be computed on candidates of other q/fq restrictions)
+      // regardless of how few/many docs match the frange
+      assertQ("query matching 1 doc w/ implicitly post-filtered frange matching all docs",
+              req("q","{!notfoo cache=false}*:*", // match all...
+                  "fq","{!frange cache=false l=30 u=30}abs(id_i1)", // ...restrict to 1 match
+                  // post filter will happily match all docs, but should only be asked about 1...
+                  "fq","{!frange cache=false l=4.5 u=4.5 v='countUsage(postfilt_match_all,4.5)'})"),
+              "//result[@numFound=1]");
+      assertEquals(1, CountUsageValueSourceParser.getAndClearCount("postfilt_match_all"));
+      //
+      assertQ("query matching all docs w/ implicitly post-filtered frange matching no docs",
+              req("q","{!notfoo cache=false}id_i1:[20 TO 39]", // match some...
+                  "fq","{!frange cache=false cost=0 l=50}abs(id_i1)", // ...regular conjunction filter rules out all
+                  // post filter will happily match all docs, but should never be asked...
+                  "fq","{!frange cache=false l=4.5 u=4.5 v='countUsage(postfilt_match_all,4.5)'})"),
+              "//result[@numFound=0]");
+      assertEquals(0, CountUsageValueSourceParser.getAndClearCount("postfilt_match_all"));
+
     } finally {
       CountUsageValueSourceParser.clearCounters();
     }

solr/core/src/test/org/apache/solr/search/QueryEqualityTest.java

@@ -370,8 +370,10 @@ public class QueryEqualityTest extends SolrTestCaseJ4 {
                                "myField","foo_i",
                                "myInner","product(4,foo_i)");
     try {
+      // NOTE: unlike most queries, frange defaultsto cost==100
       assertQueryEquals("frange", req, 
                         "{!frange l=0.2 h=20.4}sum(4,5)",
+                        "{!frange l=0.2 h=20.4 cost=100}sum(4,5)",
                         "{!frange l=$low h=$high}sum(4,$myVar)");
     } finally {
       req.close();

solr/core/src/test/org/apache/solr/search/TestFiltering.java

@@ -109,29 +109,38 @@ public class TestFiltering extends SolrTestCaseJ4 {
 
     int prevCount;
 
+    // default cost uses post filtering (for frange)
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("q","*:*", "fq","{!frange l=2 u=3 cache=false cost=100}val_i")
+    assertJQ(req("q","*:*", "fq","{!frange l=2 u=3 cache=false}val_i")
         ,"/response/numFound==2"
     );
     assertEquals(1, DelegatingCollector.setLastDelegateCount - prevCount);
 
     // The exact same query the second time will be cached by the queryCache
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("q","*:*", "fq","{!frange l=2 u=3 cache=false cost=100}val_i")
+    assertJQ(req("q","*:*", "fq","{!frange l=2 u=3 cache=false}val_i")
         ,"/response/numFound==2"
     );
     assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
 
-    // cache is true by default
+    // cache is true by default, even w/explicit low/high costs
     prevCount = DelegatingCollector.setLastDelegateCount;
     assertJQ(req("q","*:*", "fq","{!frange l=2 u=4}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
+    assertJQ(req("q","*:*", "fq","{!frange l=2 u=4 cost=0}val_i")
+        ,"/response/numFound==3"
+    );
+    assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
+    assertJQ(req("q","*:*", "fq","{!frange l=2 u=4 cost=999}val_i")
+        ,"/response/numFound==3"
+    );
+    assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
 
-    // default cost avoids post filtering
+    // no caching and explicitly low cost avoids post filtering
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("q","*:*", "fq","{!frange l=2 u=5 cache=false}val_i")
+    assertJQ(req("q","*:*", "fq","{!frange l=2 u=5 cache=false cost=0}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
@@ -139,29 +148,38 @@ public class TestFiltering extends SolrTestCaseJ4 {
 
     // now re-do the same tests w/ faceting on to get the full docset
 
+    // default cost uses post filtering (for frange)
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=6 cache=false cost=100}val_i")
+    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=6 cache=false}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(1, DelegatingCollector.setLastDelegateCount - prevCount);
 
     // since we need the docset and the filter was not cached, the collector will need to be used again
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=6 cache=false cost=100}val_i")
+    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=6 cache=false}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(1, DelegatingCollector.setLastDelegateCount - prevCount);
 
-    // cache is true by default
+    // cache is true by default, even w/explicit low/high costs
     prevCount = DelegatingCollector.setLastDelegateCount;
     assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=7}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
+    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=7 cost=0}val_i")
+        ,"/response/numFound==3"
+    );
+    assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
+    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=7 cost=999}val_i")
+        ,"/response/numFound==3"
+    );
+    assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);
 
-    // default cost avoids post filtering
+    // no caching and explicitly low cost avoids post filtering
     prevCount = DelegatingCollector.setLastDelegateCount;
-    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=8 cache=false}val_i")
+    assertJQ(req("facet","true", "facet.field","id", "q","*:*", "fq","{!frange l=2 u=8 cache=false cost=0}val_i")
         ,"/response/numFound==3"
     );
     assertEquals(0, DelegatingCollector.setLastDelegateCount - prevCount);

solr/solr-ref-guide/src/common-query-parameters.adoc

@@ -239,21 +239,25 @@ You can also use the `cost` option to control the order in which non-cached filt
 
 For very high cost filters, if `cache=false` and `cost>=100` and the query implements the `PostFilter` interface, a Collector will be requested from that query and used to filter documents after they have matched the main query and all other filter queries. There can be multiple post filters; they are also ordered by cost.
 
+For most queries the default behavior is `cost=0` -- but some types of queries such as `{!frange}` default to `cost=100`, because they are most efficient when used as a `PostFilter`.
+
 For example:
 
-This is a normal function range query used as a filter, all matching documents generated up front and cached:
+This is an example of 3 regular filters, where all matching documents generated by each are computed up front and cached independently:
+
 [source,text]
+q=some keywords
+fq=quantity_in_stock:[5 TO *]
 fq={!frange l=10 u=100}mul(popularity,price)
+fq={!frange cost=200 l=0}pow(mul(sum(1, query('tag:smartphone')), div(1,avg_rating)), 2.3)
 
-This is a function range query run in parallel with the main query like a traditional lucene filter:
+These are the same filters run w/o caching.  The simple range query on the `quantity_in_stock` field will be run in parallel with the main query like a traditional lucene filter, while the 2 `frange` filters will only be checked against each document has already matched the main query and the `quantity_in_stock` range query -- first the simpler `mul(popularity,price)` will be checked (because of it's implicit `cost=100`) and only if it matches will the final very complex filter (with it's higher `cost=200`) be checked.
 
 [source,text]
-fq={!frange l=10 u=100 cache=false}mul(popularity,price)
+q=some keywords
-
+fq={!cache=false}quantity_in_stock:[5 TO *]
-This is a function range query checked after each document that already matches the query and all other filters. This is good for really expensive function queries:
+fq={!frange cache=false l=10 u=100}mul(popularity,price)
-
+fq={!frange cache=false cost=200 l=0}pow(mul(sum(1, query('tag:smartphone')), div(1,avg_rating)), 2.3)
-[source,text]
-fq={!frange l=10 u=100 cache=false cost=100}mul(popularity,price)
 
 == logParamsList Parameter