From 3d88a72f76d2b24969974fb16eee603e838f4556 Mon Sep 17 00:00:00 2001
From: Aleksey Midenkov <midenok@gmail.com>
Date: Tue, 5 Dec 2017 03:25:34 +0300
Subject: [PATCH] SQL: fix subquery not a derived table [#365 bug 9]

Tests affected (forced mode):

main.ps \
main.user_var \
main.myisam_explain_non_select_all \
main.opt_tvc \
main.subselect \
main.subselect_no_exists_to_in \
main.derived \
main.derived_opt \
main.update
---
 mysql-test/suite/versioning/r/select.result | 4 ++++
 mysql-test/suite/versioning/t/select.test   | 4 ++++
 sql/sql_select.cc                           | 6 +++---
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/mysql-test/suite/versioning/r/select.result b/mysql-test/suite/versioning/r/select.result
index 3b0d4b74286..ef2755460c3 100644
--- a/mysql-test/suite/versioning/r/select.result
+++ b/mysql-test/suite/versioning/r/select.result
@@ -298,6 +298,10 @@ create or replace table t2 (b int) with system versioning;
 select * from t1
 where exists (select 1 from t2 where t2.b = t1.a and t2.b = t1.a);
 a
+### Issue #365, bug 9 (not a derived subquery)
+create or replace table t1 (x int) with system versioning;
+select t1.x in (select x from t1) a from t1, (select x from t1) b;
+a
 drop view v1;
 drop table t1, t2;
 call innodb_verify_vtq(28);
diff --git a/mysql-test/suite/versioning/t/select.test b/mysql-test/suite/versioning/t/select.test
index 51b10d420e8..8f8698bbfcc 100644
--- a/mysql-test/suite/versioning/t/select.test
+++ b/mysql-test/suite/versioning/t/select.test
@@ -195,6 +195,10 @@ create or replace table t2 (b int) with system versioning;
 select * from t1
 where exists (select 1 from t2 where t2.b = t1.a and t2.b = t1.a);
 
+--echo ### Issue #365, bug 9 (not a derived subquery)
+create or replace table t1 (x int) with system versioning;
+select t1.x in (select x from t1) a from t1, (select x from t1) b;
+
 drop view v1;
 drop table t1, t2;
 
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 76e8eb4f175..67f41797a12 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -791,14 +791,14 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
       if (!vers_conditions && outer_slex && slex->vers_import_outer)
       {
         TABLE_LIST* derived= slex->master_unit()->derived;
-        while (outer_slex && (!derived->vers_conditions || derived->vers_conditions.from_inner))
+        // inner SELECT may not be a derived table (derived == NULL)
+        while (derived && outer_slex && (!derived->vers_conditions || derived->vers_conditions.from_inner))
         {
           derived= outer_slex->master_unit()->derived;
           outer_slex= outer_slex->next_select_in_list();
         }
-        if (outer_slex)
+        if (derived && outer_slex && !derived->vers_conditions.from_inner)
         {
-          DBUG_ASSERT(derived);
           DBUG_ASSERT(derived->vers_conditions);
           vers_conditions= derived->vers_conditions;
         }