Experimental changes to improve optimization of DISTINCT queries.

FossilOrigin-Name: f7ba0219ef2f235543c258be736955d91ca5ecce

test/collate5.test

@@ -57,17 +57,17 @@ do_test collate5-1.1 {
   execsql {
     SELECT DISTINCT a FROM collate5t1;
   }
-} {A B N}
+} {a b n}
 do_test collate5-1.2 {
   execsql {
     SELECT DISTINCT b FROM collate5t1;
   }
-} {{} Apple apple banana}
+} {apple Apple banana {}}
 do_test collate5-1.3 {
   execsql {
     SELECT DISTINCT a, b FROM collate5t1;
   }
-} {A Apple a apple B banana N {}}
+} {a apple A Apple b banana n {}}
 
 # Ticket #3376
 #

test/e_select.test

@@ -1238,8 +1238,8 @@ do_select_tests e_select-5 {
   3.1 "SELECT x FROM h2" {One Two Three Four one two three four}
   3.2 "SELECT x FROM h1, h2 ON (x=b)" {One one Four four}
 
-  4.1 "SELECT DISTINCT x FROM h2" {four one three two}
-  4.2 "SELECT DISTINCT x FROM h1, h2 ON (x=b)" {four one}
+  4.1 "SELECT DISTINCT x FROM h2" {One Two Three Four}
+  4.2 "SELECT DISTINCT x FROM h1, h2 ON (x=b)" {One Four}
 } 
 
 # EVIDENCE-OF: R-02054-15343 For the purposes of detecting duplicate
@@ -1253,11 +1253,11 @@ do_select_tests e_select-5.5 {
 # sequence to compare text values with apply.
 #
 do_select_tests e_select-5.6 {
-  1  "SELECT DISTINCT b FROM h1"                  {I IV four i iv one}
-  2  "SELECT DISTINCT b COLLATE nocase FROM h1"   {four i iv one}
-  3  "SELECT DISTINCT x FROM h2"                  {four one three two}
+  1  "SELECT DISTINCT b FROM h1"                  {one I i four IV iv}
+  2  "SELECT DISTINCT b COLLATE nocase FROM h1"   {one I four IV}
+  3  "SELECT DISTINCT x FROM h2"                  {One Two Three Four}
   4  "SELECT DISTINCT x COLLATE binary FROM h2"   {
-    Four One Three Two four one three two
+    One Two Three Four one two three four
   }
 }
 

test/fuzzer1.test

@@ -1376,7 +1376,7 @@ do_test fuzzer1-2.3 {
        AND f2.distance<=200
        AND streetname.n>=f2.word AND streetname.n<=(f2.word || x'F7BFBFBF')
   }
-} {steelewood tallia tallu talwyn taymouth thelema trailer {tyler finley}}
+} {{tyler finley} trailer taymouth steelewood tallia tallu talwyn thelema}
 
 
 finish_test

test/insert4.test

@@ -112,7 +112,7 @@ do_test insert4-2.4.1 {
     INSERT INTO t3 SELECT DISTINCT * FROM t2;
     SELECT * FROM t3;
   }
-} {1 9 9 1}
+} {9 1 1 9}
 xferopt_test insert4-2.4.2 0
 do_test insert4-2.4.3 {
   catchsql {

test/misc5.test

@@ -505,7 +505,7 @@ ifcapable subquery {
       )  
       ORDER BY LOWER(artist) ASC;
     }
-  } {one}
+  } {two}
 }
 
 # Ticket #1370.  Do not overwrite small files (less than 1024 bytes)

test/selectB.test

@@ -355,7 +355,7 @@ for {set ii 3} {$ii <= 4} {incr ii} {
         SELECT DISTINCT (a/10) FROM t1 UNION ALL SELECT DISTINCT(d%2) FROM t2
       )
     }
-  } {0 1 0 1}
+  } {0 1 1 0}
 
   do_test selectB-$ii.20 {
     execsql {