Test cases and bug fixes applied to the ORDER BY optimization for joins.

Some test cases fail, but except for the new orderby1.test failures, all
failures appear to be issues with the tests, not with the core code.

FossilOrigin-Name: 75cda864ededb6dc0f84bd52ed3311753a58e351

test/orderby1.test

@@ -0,0 +1,155 @@
+# 2012 Sept 27
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+# This file implements regression tests for SQLite library.  The
+# focus of this file is testing that the optimizations that disable
+# ORDER BY clauses when the natural order of a query is correct.
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set ::testprefix orderby1
+
+# Generate test data for a join.  Verify that the join gets the
+# correct answer.
+#
+do_test 1.0 {
+  db eval {
+    BEGIN;
+    CREATE TABLE album(
+      aid INTEGER PRIMARY KEY,
+      title TEXT UNIQUE NOT NULL
+    );
+    CREATE TABLE track(
+      tid INTEGER PRIMARY KEY,
+      aid INTEGER NOT NULL REFERENCES album,
+      tn INTEGER NOT NULL,
+      name TEXT,
+      UNIQUE(aid, tn)
+    );
+    INSERT INTO album VALUES(1, '1-one'), (2, '2-two'), (3, '3-three');
+    INSERT INTO track VALUES
+        (NULL, 1, 1, 'one-a'),
+        (NULL, 2, 2, 'two-b'),
+        (NULL, 3, 3, 'three-c'),
+        (NULL, 1, 3, 'one-c'),
+        (NULL, 2, 1, 'two-a'),
+        (NULL, 3, 1, 'three-a');
+    COMMIT;
+  }
+} {}
+do_test 1.1a {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title, tn
+  }
+} {one-a one-c two-a two-b three-a three-c}
+
+# Verify that the ORDER BY clause is optimized out
+#
+do_test 1.1b {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title, tn
+  }
+} {~/ORDER BY/}  ;# ORDER BY optimized out
+
+# The same query with ORDER BY clause optimization disabled via + operators
+# should give exactly the same answer.
+#
+do_test 1.2a {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY +title, +tn
+  }
+} {one-a one-c two-a two-b three-a three-c}
+
+# The output is sorted manually in this case.
+#
+do_test 1.2b {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY +title, +tn
+  }
+} {/ORDER BY/}   ;# separate sorting pass due to "+" on ORDER BY terms
+
+# The same query with ORDER BY optimizations turned off via built-in test.
+#
+do_test 1.3a {
+  optimization_control db order-by-idx-join 0
+  db cache flush
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title, tn
+  }
+} {one-a one-c two-a two-b three-a three-c}
+do_test 1.3b {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title, tn
+  }
+} {/ORDER BY/}   ;# separate sorting pass due to disabled optimization
+optimization_control db all 1
+db cache flush
+
+# Reverse order sorts
+#
+do_test 1.4a {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title DESC, tn
+  }
+} {three-a three-c two-a two-b one-a one-c}
+do_test 1.4b {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY +title DESC, +tn
+  }
+} {three-a three-c two-a two-b one-a one-c}  ;# verify same order after sorting
+do_test 1.4c {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title DESC, tn
+  }
+} {~/ORDER BY/}  ;# ORDER BY optimized-out
+
+
+do_test 1.5a {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title, tn DESC
+  }
+} {one-c one-a two-b two-a three-c three-a}
+do_test 1.5b {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY +title, +tn DESC
+  }
+} {one-c one-a two-b two-a three-c three-a}  ;# verify same order after sorting
+do_test 1.5c {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title DESC, tn
+  }
+} {~/ORDER BY/}  ;# ORDER BY optimized-out
+
+do_test 1.6a {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title DESC, tn DESC
+  }
+} {three-c three-a two-b two-a one-c one-a}
+do_test 1.6b {
+  db eval {
+    SELECT name FROM album JOIN track USING (aid) ORDER BY +title DESC, +tn DESC
+  }
+} {three-c three-a two-b two-a one-c one-a}  ;# verify same order after sorting
+do_test 1.6c {
+  db eval {
+    EXPLAIN QUERY PLAN
+    SELECT name FROM album JOIN track USING (aid) ORDER BY title DESC, tn DESC
+  }
+} {~/ORDER BY/}  ;# ORDER BY optimized-out
+
+
+finish_test