A few simple test cases for the ORDER BY LIMIT optimization.

FossilOrigin-Name: 08849eab0f6ef29eaf6d2ce9c692de9b953dbd27

diff --git a/manifest b/manifest
index 39cec630cefa601e7b5a962eb9b4b7f1e1e5e3a2..3f35f82e000b5f7a1e2b77190ab12c72e5b8c017 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Appears\sto\swork\snow.\s\sNeeds\stest\scases,\smore\scomments,\sand\scode\soptimization.
-D 2016-05-19T22:40:04.862
+C A\sfew\ssimple\stest\scases\sfor\sthe\sORDER\sBY\sLIMIT\soptimization.
+D 2016-05-20T00:21:42.961
 F Makefile.in f59e0763ff448719fc1bd25513882b0567286317
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 306d73e854b1a92ea06e5d1e637faa5c44de53c7
@@ -878,6 +878,7 @@ F test/like.test 81632c437a947bf1f7130b19537da6a1a844806a
 F test/like2.test 3b2ee13149ba4a8a60b59756f4e5d345573852da
 F test/like3.test 3608a2042b6f922f900fbfd5d3ce4e7eca57f7c4
 F test/limit.test 0c99a27a87b14c646a9d583c7c89fd06c352663e
+F test/limit2.test 55c9f4d08c89311e00afd75045ee1a2aca205cb4
 F test/loadext.test 42a3b8166dfcadcb0e0c8710dc520d97c31a8b98
 F test/loadext2.test 0408380b57adca04004247179837a18e866a74f7
 F test/lock.test be4fe08118fb988fed741f429b7dd5d65e1c90db
@@ -1489,7 +1490,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 852d1eda6ecca1171f6ed800b06f5b4854672002
-R 664cd7ecddde2637b78c890f65cd5e15
+P 990fe50c9182f74c9b54a12602c4c30d891273e6
+R b3508f6593a9fbd22c3973de159c4a41
 U drh
-Z a9319f97e8df1737542ca3813ad100bc
+Z 1bcf9218783f46102cc72fd7dcd4a1fb

diff --git a/manifest.uuid b/manifest.uuid
index 2ec1166f5a273b383ada97e4bd27b5fe954fa302..277784dcaf668c4146d3187784f7d92517aca2c1 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-990fe50c9182f74c9b54a12602c4c30d891273e6
\ No newline at end of file
+08849eab0f6ef29eaf6d2ce9c692de9b953dbd27
\ No newline at end of file

diff --git a/test/limit2.test b/test/limit2.test
new file mode 100644 (file)
index 0000000..f415f32
--- /dev/null
+++ b/test/limit2.test
@@ -0,0 +1,82 @@
+# 2016-05-20
+#
+# 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 the LIMIT in combination with ORDER BY
+# and in particular, the optimizations in the inner loop that cause an
+# early exit of the inner loop when the LIMIT is reached and the inner
+# loop is emitting rows in ORDER BY order.
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test limit2-100 {
+  CREATE TABLE t1(a,b);
+  WITH RECURSIVE c(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM c WHERE x<1000)
+    INSERT INTO t1(a,b) SELECT 1, (x*17)%1000 + 1000 FROM c;
+  INSERT INTO t1(a,b) VALUES(2,2),(3,1006),(4,4),(5,9999);
+  CREATE INDEX t1ab ON t1(a,b);
+}
+set sqlite_search_count 0
+do_execsql_test limit2-100.1 {
+  SELECT a, b, '|' FROM t1 WHERE a IN (2,4,5,3,1) ORDER BY b LIMIT 5;
+} {2 2 | 4 4 | 1 1000 | 1 1001 | 1 1002 |}
+set fast_count $sqlite_search_count
+set sqlite_search_count 0
+do_execsql_test limit2-100.2 {
+  SELECT a, b, '|' FROM t1 WHERE a IN (2,4,5,3,1) ORDER BY +b LIMIT 5;
+} {2 2 | 4 4 | 1 1000 | 1 1001 | 1 1002 |}
+do_test limit2-100.3 {
+  set slow_count $sqlite_search_count
+  expr {$fast_count < 0.02*$slow_count}
+} {1}
+
+do_execsql_test limit2-110 {
+  CREATE TABLE t2(x,y);
+  INSERT INTO t2(x,y) VALUES('a',1),('a',2),('a',3),('a',4);
+  INSERT INTO t2(x,y) VALUES('b',1),('c',2),('d',3),('e',4);
+  CREATE INDEX t2xy ON t2(x,y);
+}
+set sqlite_search_count 0
+do_execsql_test limit2-110.1 {
+  SELECT a, b, '|' FROM t2, t1 WHERE t2.x='a' AND t1.a=t2.y ORDER BY t1.b LIMIT 5;
+} {2 2 | 4 4 | 1 1000 | 1 1001 | 1 1002 |}
+set fast_count $sqlite_search_count
+set sqlite_search_count 0
+do_execsql_test limit2-110.2 {
+  SELECT a, b, '|' FROM t2, t1 WHERE t2.x='a' AND t1.a=t2.y ORDER BY +t1.b LIMIT 5;
+} {2 2 | 4 4 | 1 1000 | 1 1001 | 1 1002 |}
+set slow_count $sqlite_search_count
+do_test limit2-110.3 {
+  expr {$fast_count < 0.02*$slow_count}
+} {1}
+
+do_execsql_test limit2-120 {
+  DROP INDEX t1ab;
+  CREATE INDEX t1ab ON t1(a,b DESC);
+}
+set sqlite_search_count 0
+do_execsql_test limit2-120.1 {
+  SELECT a, b, '|' FROM t1 WHERE a IN (2,4,5,3,1) ORDER BY b DESC LIMIT 5;
+} {5 9999 | 1 1999 | 1 1998 | 1 1997 | 1 1996 |}
+set fast_count $sqlite_search_count
+set sqlite_search_count 0
+do_execsql_test limit2-120.2 {
+  SELECT a, b, '|' FROM t1 WHERE a IN (2,4,5,3,1) ORDER BY +b DESC LIMIT 5;
+} {5 9999 | 1 1999 | 1 1998 | 1 1997 | 1 1996 |}
+do_test limit2-120.3 {
+  set slow_count $sqlite_search_count
+  expr {$fast_count < 0.02*$slow_count}
+} {1}
+
+
+
+finish_test