From: dan <dan@noemail.net>
Date: Tue, 20 Jun 2017 17:43:26 +0000 (+0000)
Subject: Ensure that the query planner knows that any column of a flattened LEFT JOIN
X-Git-Tag: version-3.20.0~187
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bd11a2acbb29dd6548dc49961d78694c5e0c3f7e;p=thirdparty%2Fsqlite.git

Ensure that the query planner knows that any column of a flattened LEFT JOIN
can be NULL even if that column is labeled with "NOT NULL".
Fix for ticket [892fc34f173e99d8].

FossilOrigin-Name: 483462682d3a57fb9dd85b4772596e9738f1694a454b8ebbc480b9452733e88d
---

diff --git a/manifest b/manifest
index 7ff1732e8e..4b98d1d665 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\smissing\scomma\sin\sthe\sprevious\scheck-in.
-D 2017-06-17T18:49:50.823
+C Ensure\sthat\sthe\squery\splanner\sknows\sthat\sany\scolumn\sof\sa\sflattened\sLEFT\sJOIN\ncan\sbe\sNULL\seven\sif\sthat\scolumn\sis\slabeled\swith\s"NOT\sNULL".\nFix\sfor\sticket\s[892fc34f173e99d8].
+D 2017-06-20T17:43:26.613
 F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
@@ -405,7 +405,7 @@ F src/printf.c 8757834f1b54dae512fb25eb1acc8e94a0d15dd2290b58f2563f65973265adb2
 F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c adf3ef9843135b1383321ad751f16f5a40c3f37925154555a3e61653d2a954e8
 F src/rowset.c 7b7e7e479212e65b723bf40128c7b36dc5afdfac
-F src/select.c 0d2afdbdba5fbc61432c5454a35e0236e7aa4aa3756986a7d51b81a508e8083a
+F src/select.c 35ccfae64cecfa843d54a5898c4ab7d6595ce03d147267fa5eecdc8eab39cd6a
 F src/shell.c bcd3358ad6cb3f3dc7ec76ad3bd8191f123ed2425360c5c48fe431780eceb729
 F src/sqlite.h.in 67fa8bd29808e7988e0ce36c8d4c6043eb1727f94522fc612687aa5af51931e6
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
@@ -908,7 +908,7 @@ F test/ioerr3.test d3cec5e1a11ad6d27527d0d38573fbff14c71bdd
 F test/ioerr4.test f130fe9e71008577b342b8874d52984bd04ede2c
 F test/ioerr5.test 2edfa4fb0f896f733071303b42224df8bedd9da4
 F test/ioerr6.test a395a6ab144b26a9e3e21059a1ab6a7149cca65b
-F test/join.test 302f164f4a41c240d16ebd780762834233be77b852f15232c9a48a6fe37ac0fa
+F test/join.test 442c462eea85cf065d70a663c626b780a95af6e11585d909bb63b87598afe678
 F test/join2.test a48f723c5692e2cbb23a9297ac2720cb77d51a70
 F test/join3.test 6f0c774ff1ba0489e6c88a3e77b9d3528fb4fda0
 F test/join4.test 1a352e4e267114444c29266ce79e941af5885916
@@ -1583,7 +1583,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 9a443397a6b110f60cae32e1f758914d72931e16ddb423e4d4a119df526bf340
-R 48cf46cf5e03c592f1eb729aae9e27b1
-U drh
-Z 1075564756c6da5b66b28900b7b4b32b
+P f3db02f49073c3f08c3fd7816d85e5472d5e22df20d862fe4886eb2a97efb15f
+R 65c6dcf56f692aabb1488a88a7fa82bd
+U dan
+Z a6ca5a5b1b0df383164124d4a74591e8
diff --git a/manifest.uuid b/manifest.uuid
index 64f264fc2c..dc950391b8 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f3db02f49073c3f08c3fd7816d85e5472d5e22df20d862fe4886eb2a97efb15f
\ No newline at end of file
+483462682d3a57fb9dd85b4772596e9738f1694a454b8ebbc480b9452733e88d
\ No newline at end of file
diff --git a/src/select.c b/src/select.c
index 6c99776e19..74747fadc2 100644
--- a/src/select.c
+++ b/src/select.c
@@ -3205,9 +3205,12 @@ static Expr *substExpr(
           pCopy = &ifNullRow;
         }
         pNew = sqlite3ExprDup(db, pCopy, 0);
-        if( pNew && (pExpr->flags & EP_FromJoin) ){
+        if( pNew && pSubst->isLeftJoin ){
+          ExprSetProperty(pNew, EP_CanBeNull);
+        }
+        if( pNew && ExprHasProperty(pExpr,EP_FromJoin) ){
           pNew->iRightJoinTable = pExpr->iRightJoinTable;
-          pNew->flags |= EP_FromJoin;
+          ExprSetProperty(pNew, EP_FromJoin);
         }
         sqlite3ExprDelete(db, pExpr);
         pExpr = pNew;
@@ -3500,7 +3503,7 @@ static int flattenSubquery(
   **
   ** If the subquery is the right operand of a LEFT JOIN, then the outer
   ** query cannot be an aggregate.  This is an artifact of the way aggregates
-  ** are processed - there is not mechanism to determine if the LEFT JOIN
+  ** are processed - there is no mechanism to determine if the LEFT JOIN
   ** table should be all-NULL.
   **
   ** See also tickets #306, #350, and #3300.
diff --git a/test/join.test b/test/join.test
index ac536df4e5..4df586d8ab 100644
--- a/test/join.test
+++ b/test/join.test
@@ -763,4 +763,21 @@ do_execsql_test join-14.12 {
   SELECT *, '|' FROM t3 LEFT JOIN v2 ON a=x ORDER BY b;
 } {4 {} {} | 2 2 1 |}
 
+# Verify the fix for ticket
+# https://www.sqlite.org/src/info/892fc34f173e99d8
+#
+db close
+sqlite3 db :memory:
+do_execsql_test join-14.20 {
+  CREATE TABLE t1(id INTEGER PRIMARY KEY);
+  CREATE TABLE t2(id INTEGER PRIMARY KEY, c2 INTEGER);
+  CREATE TABLE t3(id INTEGER PRIMARY KEY, c3 INTEGER);
+  INSERT INTO t1(id) VALUES(456);
+  INSERT INTO t3(id) VALUES(1),(2);
+  SELECT t1.id, x2.id, x3.id
+  FROM t1
+  LEFT JOIN (SELECT * FROM t2) AS x2 ON t1.id=x2.c2
+  LEFT JOIN t3 AS x3 ON x2.id=x3.c3;
+} {456 {} {}}
+
 finish_test