[sql] Import reference version of SQLite 3.8.7.4.

third_party/sqlite/sqlite-src-3080704/test/skipscan3.test

+# 2014-08-20
+#
+# 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 tests of the "skip-scan" query strategy.
+# In particular, this file looks at skipping intermediate terms
+# in an index.  For example, if (a,b,c) are indexed, and we have
+# "WHERE a=?1 AND c=?2" - verify that skip-scan can still be used.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test skipscan3-1.1 {
+  CREATE TABLE t1(a,b,c,d,PRIMARY KEY(a,b,c));
+  WITH RECURSIVE
+    c(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM c WHERE x<1000)
+  INSERT INTO t1(a,b,c,d)
+    SELECT 1, 1, x, printf('x%04d',x) FROM c;
+  ANALYZE;
+} {}
+
+# This version has long used skip-scan because of the "+a"
+#
+do_execsql_test skipscan3-1.2eqp {
+  EXPLAIN QUERY PLAN SELECT d FROM t1 WHERE +a=1 AND c=32;
+} {/*ANY(a) AND ANY(b)*/}
+do_execsql_test skipscan3-1.2 {
+  SELECT d FROM t1 WHERE +a=1 AND c=32;
+} {x0032}
+
+# This version (with "a" instead of "+a") should use skip-scan but
+# did not prior to changes implemented on 2014-08-20
+#
+do_execsql_test skipscan3-1.3eqp {
+  EXPLAIN QUERY PLAN SELECT d FROM t1 WHERE a=1 AND c=32;
+} {/*ANY(a) AND ANY(b)*/}
+do_execsql_test skipscan3-1.3 {
+  SELECT d FROM t1 WHERE a=1 AND c=32;
+} {x0032}
+
+# Repeat the test on a WITHOUT ROWID table
+#
+do_execsql_test skipscan3-2.1 {
+  CREATE TABLE t2(a,b,c,d,PRIMARY KEY(a,b,c)) WITHOUT ROWID;
+  WITH RECURSIVE
+    c(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM c WHERE x<1000)
+  INSERT INTO t2(a,b,c,d)
+    SELECT 1, 1, x, printf('x%04d',x) FROM c;
+  ANALYZE;
+} {}
+do_execsql_test skipscan3-2.2eqp {
+  EXPLAIN QUERY PLAN SELECT d FROM t2 WHERE +a=1 AND c=32;
+} {/*ANY(a) AND ANY(b)*/}
+do_execsql_test skipscan3-2.2 {
+  SELECT d FROM t2 WHERE +a=1 AND c=32;
+} {x0032}
+do_execsql_test skipscan3-2.3eqp {
+  EXPLAIN QUERY PLAN SELECT d FROM t2 WHERE a=1 AND c=32;
+} {/*ANY(a) AND ANY(b)*/}
+do_execsql_test skipscan3-2.3 {
+  SELECT d FROM t2 WHERE a=1 AND c=32;
+} {x0032}
+
+  
+finish_test