Where possible, transform the DISTINCT qualifier to a GROUP BY clause. GROUP BY clauses may be optimized by indices, DISTINCT qualifiers cannot. (CVS 4538)

FossilOrigin-Name: e56331234791cf3d830a30e4cfa66682bdf2eed1

test/collate5.test

@@ -14,7 +14,7 @@
 # SELECT statements that use user-defined collation sequences. Also
 # GROUP BY clauses that use user-defined collation sequences.
 #
-# $Id: collate5.test,v 1.5 2005/09/07 22:48:16 drh Exp $
+# $Id: collate5.test,v 1.6 2007/11/12 15:29:19 danielk1977 Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -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 {}}
 
 # The remainder of this file tests compound SELECT statements.
 # Omit it if the library is compiled such that they are omitted.

test/insert4.test

@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing the INSERT transfer optimization.
 #
-# $Id: insert4.test,v 1.8 2007/10/09 08:29:32 danielk1977 Exp $
+# $Id: insert4.test,v 1.9 2007/11/12 15:29:19 danielk1977 Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -112,7 +112,7 @@ do_test insert4-2.4.1 {
     INSERT INTO t3 SELECT DISTINCT * FROM t2;
     SELECT * FROM t3;
   }
-} {9 1 1 9}
+} {1 9 9 1}
 xferopt_test insert4-2.4.2 0
 do_test insert4-2.4.3 {
   catchsql {

test/misc5.test

@@ -13,7 +13,7 @@
 # This file implements tests for miscellanous features that were
 # left out of other test files.
 #
-# $Id: misc5.test,v 1.17 2007/09/12 17:01:45 danielk1977 Exp $
+# $Id: misc5.test,v 1.18 2007/11/12 15:29:19 danielk1977 Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -481,8 +481,18 @@ ifcapable subquery {
         SELECT songid    
         FROM songs    
         WHERE LOWER(artist) = (    
+          -- This sub-query is indeterminate. Because there is no ORDER BY,
+          -- it may return 'one', 'two' or 'three'. Because of this, the
+	  -- outermost parent query may correctly return any of 'one', 'two' 
+          -- or 'three' as well.
           SELECT DISTINCT LOWER(artist)    
           FROM (      
+            -- This sub-query returns the table:
+            --
+            --     two      14
+            --     one      10
+            --     three    5
+            --
             SELECT DISTINCT artist,sum(timesplayed) AS total      
             FROM songs      
             GROUP BY LOWER(artist)      
@@ -495,7 +505,7 @@ ifcapable subquery {
       )  
       ORDER BY LOWER(artist) ASC;
     }
-  } {two}
+  } {one}
 }
 
 # Ticket #1370.  Do not overwrite small files (less than 1024 bytes)