Merge 10.4 into 10.5

12 files changed, 368 insertions, 153 deletions

diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index cdfde2cc3ee..d52f44f9b95 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -9182,7 +9182,6 @@ int ha_partition::extra(enum ha_extra_function operation)
   case HA_EXTRA_STARTING_ORDERED_INDEX_SCAN:
   case HA_EXTRA_BEGIN_ALTER_COPY:
   case HA_EXTRA_END_ALTER_COPY:
-  case HA_EXTRA_FAKE_START_STMT:
     DBUG_RETURN(loop_partitions(extra_cb, &operation));
   default:
   {
diff --git a/sql/handler.h b/sql/handler.h
index b0a90f24494..b00643d0ace 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -1799,6 +1799,12 @@ handlerton *ha_default_tmp_handlerton(THD *thd);
 */
 #define HTON_TRANSACTIONAL_AND_NON_TRANSACTIONAL (1 << 17)
 
+/*
+  Table requires and close and reopen after truncate
+  If the handler has HTON_CAN_RECREATE, this flag is not used
+*/
+#define HTON_REQUIRES_CLOSE_AFTER_TRUNCATE (1 << 18)
+
 class Ha_trx_info;
 
 struct THD_TRANS
diff --git a/sql/item.cc b/sql/item.cc
index f818a9f02e7..7caa9e41e2f 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -9372,7 +9372,7 @@ bool Item_default_value::fix_fields(THD *thd, Item **items)
   def_field->reset_fields();
   // If non-constant default value expression or a blob
   if (def_field->default_value &&
-      (def_field->default_value->flags || def_field->flags & BLOB_FLAG))
+      (def_field->default_value->flags || (def_field->flags & BLOB_FLAG)))
   {
     uchar *newptr= (uchar*) thd->alloc(1+def_field->pack_length());
     if (!newptr)
@@ -9476,11 +9476,60 @@ int Item_default_value::save_in_field(Field *field_arg, bool no_conversions)
   return Item_field::save_in_field(field_arg, no_conversions);
 }
 
+double Item_default_value::val_result()
+{
+  calculate();
+  return Item_field::val_result();
+}
+
+longlong Item_default_value::val_int_result()
+{
+  calculate();
+  return Item_field::val_int_result();
+}
+
+String *Item_default_value::str_result(String* tmp)
+{
+  calculate();
+  return Item_field::str_result(tmp);
+}
+
+bool Item_default_value::val_bool_result()
+{
+  calculate();
+  return Item_field::val_bool_result();
+}
+
+bool Item_default_value::is_null_result()
+{
+  calculate();
+  return Item_field::is_null_result();
+}
+
+my_decimal *Item_default_value::val_decimal_result(my_decimal *decimal_value)
+{
+  calculate();
+  return Item_field::val_decimal_result(decimal_value);
+}
+
+bool Item_default_value::get_date_result(THD *thd, MYSQL_TIME *ltime,
+                                         date_mode_t fuzzydate)
+{
+  calculate();
+  return Item_field::get_date_result(thd, ltime, fuzzydate);
+}
+
+bool Item_default_value::val_native_result(THD *thd, Native *to)
+{
+  calculate();
+  return Item_field::val_native_result(thd, to);
+}
+
 table_map Item_default_value::used_tables() const
 {
   if (!field || !field->default_value)
     return static_cast<table_map>(0);
-  if (!field->default_value->expr)                      // not fully parsed field
+  if (!field->default_value->expr)           // not fully parsed field
     return static_cast<table_map>(RAND_TABLE_BIT);
   return field->default_value->expr->used_tables();
 }
diff --git a/sql/item.h b/sql/item.h
index 03c5ad06fa9..2a87081584d 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -2,7 +2,7 @@
 #define SQL_ITEM_INCLUDED
 
 /* Copyright (c) 2000, 2017, Oracle and/or its affiliates.
-   Copyright (c) 2009, 2020, MariaDB Corporation.
+   Copyright (c) 2009, 2021, MariaDB Corporation.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -6428,6 +6428,17 @@ public:
   my_decimal *val_decimal(my_decimal *decimal_value);
   bool get_date(THD *thd, MYSQL_TIME *ltime,date_mode_t fuzzydate);
   bool val_native(THD *thd, Native *to);
+  bool val_native_result(THD *thd, Native *to);
+
+  /* Result variants */
+  double val_result();
+  longlong val_int_result();
+  String *str_result(String* tmp);
+  my_decimal *val_decimal_result(my_decimal *val);
+  bool val_bool_result();
+  bool is_null_result();
+  bool get_date_result(THD *thd, MYSQL_TIME *ltime, date_mode_t fuzzydate);
+
   bool send(Protocol *protocol, st_value *buffer);
   int save_in_field(Field *field_arg, bool no_conversions);
   bool save_in_param(THD *thd, Item_param *param)
@@ -6456,6 +6467,8 @@ public:
   }
 
   Item *transform(THD *thd, Item_transformer transformer, uchar *args);
+  Field *create_tmp_field_ex(MEM_ROOT *root, TABLE *table, Tmp_field_src *src,
+                             const Tmp_field_param *param);
 };
 
 
diff --git a/sql/sql_admin.cc b/sql/sql_admin.cc
index ee7226afd0b..3f5b15715f9 100644
--- a/sql/sql_admin.cc
+++ b/sql/sql_admin.cc
@@ -1395,7 +1395,9 @@ bool Sql_cmd_analyze_table::execute(THD *thd)
     /*
       Presumably, ANALYZE and binlog writing doesn't require synchronization
     */
+    thd->get_stmt_da()->set_overwrite_status(true);
     res= write_bin_log(thd, TRUE, thd->query(), thd->query_length());
+    thd->get_stmt_da()->set_overwrite_status(false);
   }
   m_lex->first_select_lex()->table_list.first= first_table;
   m_lex->query_tables= first_table;
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index cb960a89cb6..e7fe0b39e3a 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -3346,6 +3346,146 @@ bool Sql_cmd_call::execute(THD *thd)
 
 
 /**
+  Check whether the SQL statement being processed is prepended by
+  SET STATEMENT clause and handle variables assignment if it is.
+
+  @param thd  thread handle
+  @param lex  current lex
+
+  @return false in case of success, true in case of error.
+*/
+
+bool run_set_statement_if_requested(THD *thd, LEX *lex)
+{
+  if (!lex->stmt_var_list.is_empty() && !thd->slave_thread)
+  {
+    Query_arena backup;
+    DBUG_PRINT("info", ("SET STATEMENT %d vars", lex->stmt_var_list.elements));
+
+    lex->old_var_list.empty();
+    List_iterator_fast<set_var_base> it(lex->stmt_var_list);
+    set_var_base *var;
+
+    if (lex->set_arena_for_set_stmt(&backup))
+      return true;
+
+    MEM_ROOT *mem_root= thd->mem_root;
+    while ((var= it++))
+    {
+      DBUG_ASSERT(var->is_system());
+      set_var *o= NULL, *v= (set_var*)var;
+      if (!v->var->is_set_stmt_ok())
+      {
+        my_error(ER_SET_STATEMENT_NOT_SUPPORTED, MYF(0), v->var->name.str);
+        lex->reset_arena_for_set_stmt(&backup);
+        lex->old_var_list.empty();
+        lex->free_arena_for_set_stmt();
+        return true;
+      }
+      if (v->var->session_is_default(thd))
+        o= new set_var(thd,v->type, v->var, &v->base, NULL);
+      else
+      {
+        switch (v->var->option.var_type & GET_TYPE_MASK)
+        {
+          case GET_BOOL:
+          case GET_INT:
+          case GET_LONG:
+          case GET_LL:
+          {
+            bool null_value;
+            longlong val= v->var->val_int(&null_value, thd, v->type, &v->base);
+            o= new set_var(thd, v->type, v->var, &v->base,
+                           (null_value ?
+                            (Item *) new (mem_root) Item_null(thd) :
+                            (Item *) new (mem_root) Item_int(thd, val)));
+          }
+          break;
+          case GET_UINT:
+          case GET_ULONG:
+          case GET_ULL:
+          {
+            bool null_value;
+            ulonglong val= v->var->val_int(&null_value, thd, v->type, &v->base);
+            o= new set_var(thd, v->type, v->var, &v->base,
+                           (null_value ?
+                            (Item *) new (mem_root) Item_null(thd) :
+                            (Item *) new (mem_root) Item_uint(thd, val)));
+          }
+          break;
+          case GET_DOUBLE:
+          {
+            bool null_value;
+            double val= v->var->val_real(&null_value, thd, v->type, &v->base);
+            o= new set_var(thd, v->type, v->var, &v->base,
+                           (null_value ?
+                            (Item *) new (mem_root) Item_null(thd) :
+                            (Item *) new (mem_root) Item_float(thd, val, 1)));
+          }
+          break;
+          default:
+          case GET_NO_ARG:
+          case GET_DISABLED:
+            DBUG_ASSERT(0);
+            /* fall through */
+          case 0:
+          case GET_FLAGSET:
+          case GET_ENUM:
+          case GET_SET:
+          case GET_STR:
+          case GET_STR_ALLOC:
+          {
+            char buff[STRING_BUFFER_USUAL_SIZE];
+            String tmp(buff, sizeof(buff), v->var->charset(thd)),*val;
+            val= v->var->val_str(&tmp, thd, v->type, &v->base);
+            if (val)
+            {
+              Item_string *str=
+		new (mem_root) Item_string(thd, v->var->charset(thd),
+                                           val->ptr(), val->length());
+              o= new set_var(thd, v->type, v->var, &v->base, str);
+            }
+            else
+              o= new set_var(thd, v->type, v->var, &v->base,
+                             new (mem_root) Item_null(thd));
+          }
+          break;
+        }
+      }
+      DBUG_ASSERT(o);
+      lex->old_var_list.push_back(o, thd->mem_root);
+    }
+    lex->reset_arena_for_set_stmt(&backup);
+
+    if (lex->old_var_list.is_empty())
+      lex->free_arena_for_set_stmt();
+
+    if (thd->is_error() ||
+        sql_set_variables(thd, &lex->stmt_var_list, false))
+    {
+      if (!thd->is_error())
+        my_error(ER_WRONG_ARGUMENTS, MYF(0), "SET");
+      lex->restore_set_statement_var();
+      return true;
+    }
+    /*
+      The value of last_insert_id is remembered in THD to be written to binlog
+      when it's used *the first time* in the statement. But SET STATEMENT
+      must read the old value of last_insert_id to be able to restore it at
+      the end. This should not count at "reading of last_insert_id" and
+      should not remember last_insert_id for binlog. That is, it should clear
+      stmt_depends_on_first_successful_insert_id_in_prev_stmt flag.
+    */
+    if (!thd->in_sub_stmt)
+    {
+      thd->stmt_depends_on_first_successful_insert_id_in_prev_stmt= 0;
+    }
+  }
+  return false;
+}
+
+
+/**
   Execute command saved in thd and lex->sql_command.
 
   @param thd                       Thread handle
@@ -3631,127 +3771,13 @@ mysql_execute_command(THD *thd)
   thd->get_binlog_format(&orig_binlog_format,
                          &orig_current_stmt_binlog_format);
 
-  if (!lex->stmt_var_list.is_empty() && !thd->slave_thread)
-  {
-    Query_arena backup;
-    DBUG_PRINT("info", ("SET STATEMENT %d vars", lex->stmt_var_list.elements));
-
-    lex->old_var_list.empty();
-    List_iterator_fast<set_var_base> it(lex->stmt_var_list);
-    set_var_base *var;
-
-    if (lex->set_arena_for_set_stmt(&backup))
-      goto error;
-
-    MEM_ROOT *mem_root= thd->mem_root;
-    while ((var= it++))
-    {
-      DBUG_ASSERT(var->is_system());
-      set_var *o= NULL, *v= (set_var*)var;
-      if (!v->var->is_set_stmt_ok())
-      {
-        my_error(ER_SET_STATEMENT_NOT_SUPPORTED, MYF(0), v->var->name.str);
-        lex->reset_arena_for_set_stmt(&backup);
-        lex->old_var_list.empty();
-        lex->free_arena_for_set_stmt();
-        goto error;
-      }
-      if (v->var->session_is_default(thd))
-          o= new set_var(thd,v->type, v->var, &v->base, NULL);
-      else
-      {
-        switch (v->var->option.var_type & GET_TYPE_MASK)
-        {
-        case GET_BOOL:
-        case GET_INT:
-        case GET_LONG:
-        case GET_LL:
-          {
-            bool null_value;
-            longlong val= v->var->val_int(&null_value, thd, v->type, &v->base);
-            o= new set_var(thd, v->type, v->var, &v->base,
-                           (null_value ?
-                            (Item *) new (mem_root) Item_null(thd) :
-                            (Item *) new (mem_root) Item_int(thd, val)));
-          }
-          break;
-        case GET_UINT:
-        case GET_ULONG:
-        case GET_ULL:
-          {
-            bool null_value;
-            ulonglong val= v->var->val_int(&null_value, thd, v->type, &v->base);
-            o= new set_var(thd, v->type, v->var, &v->base,
-                           (null_value ?
-                            (Item *) new (mem_root) Item_null(thd) :
-                            (Item *) new (mem_root) Item_uint(thd, val)));
-          }
-          break;
-        case GET_DOUBLE:
-          {
-            bool null_value;
-            double val= v->var->val_real(&null_value, thd, v->type, &v->base);
-            o= new set_var(thd, v->type, v->var, &v->base,
-                           (null_value ?
-                            (Item *) new (mem_root) Item_null(thd) :
-                            (Item *) new (mem_root) Item_float(thd, val, 1)));
-          }
-          break;
-        default:
-        case GET_NO_ARG:
-        case GET_DISABLED:
-          DBUG_ASSERT(0);
-          /* fall through */
-        case 0:
-        case GET_FLAGSET:
-        case GET_ENUM:
-        case GET_SET:
-        case GET_STR:
-        case GET_STR_ALLOC:
-          {
-            char buff[STRING_BUFFER_USUAL_SIZE];
-            String tmp(buff, sizeof(buff), v->var->charset(thd)),*val;
-            val= v->var->val_str(&tmp, thd, v->type, &v->base);
-            if (val)
-            {
-              Item_string *str= new (mem_root) Item_string(thd, v->var->charset(thd),
-                                                val->ptr(), val->length());
-              o= new set_var(thd, v->type, v->var, &v->base, str);
-            }
-            else
-              o= new set_var(thd, v->type, v->var, &v->base,
-                             new (mem_root) Item_null(thd));
-          }
-          break;
-        }
-      }
-      DBUG_ASSERT(o);
-      lex->old_var_list.push_back(o, thd->mem_root);
-    }
-    lex->reset_arena_for_set_stmt(&backup);
-    if (lex->old_var_list.is_empty())
-      lex->free_arena_for_set_stmt();
-    if (thd->is_error() ||
-        (res= sql_set_variables(thd, &lex->stmt_var_list, false)))
-    {
-      if (!thd->is_error())
-        my_error(ER_WRONG_ARGUMENTS, MYF(0), "SET");
-      lex->restore_set_statement_var();
-      goto error;
-    }
-    /*
-      The value of last_insert_id is remembered in THD to be written to binlog
-      when it's used *the first time* in the statement. But SET STATEMENT
-      must read the old value of last_insert_id to be able to restore it at
-      the end. This should not count at "reading of last_insert_id" and
-      should not remember last_insert_id for binlog. That is, it should clear
-      stmt_depends_on_first_successful_insert_id_in_prev_stmt flag.
-    */
-    if (!thd->in_sub_stmt)
-    {
-      thd->stmt_depends_on_first_successful_insert_id_in_prev_stmt= 0;
-    }
-  }
+  /*
+    Assign system variables with values specified by the clause
+    SET STATEMENT var1=value1 [, var2=value2, ...] FOR <statement>
+    if they are any.
+  */
+  if (run_set_statement_if_requested(thd, lex))
+    goto error;
 
   if (thd->lex->mi.connection_name.str == NULL)
       thd->lex->mi.connection_name= thd->variables.default_master_connection;
diff --git a/sql/sql_parse.h b/sql/sql_parse.h
index 0e5cc7f4bad..ac5786dbaa0 100644
--- a/sql/sql_parse.h
+++ b/sql/sql_parse.h
@@ -100,6 +100,7 @@ void mysql_init_multi_delete(LEX *lex);
 bool multi_delete_set_locks_and_link_aux_tables(LEX *lex);
 void create_table_set_open_action_and_adjust_tables(LEX *lex);
 int bootstrap(MYSQL_FILE *file);
+bool run_set_statement_if_requested(THD *thd, LEX *lex);
 int mysql_execute_command(THD *thd);
 bool do_command(THD *thd);
 bool dispatch_command(enum enum_server_command command, THD *thd,
diff --git a/sql/sql_prepare.cc b/sql/sql_prepare.cc
index 21c8f739dd2..33ced717ab9 100644
--- a/sql/sql_prepare.cc
+++ b/sql/sql_prepare.cc
@@ -4260,6 +4260,16 @@ bool Prepared_statement::prepare(const char *packet, uint packet_len)
   */
   MDL_savepoint mdl_savepoint= thd->mdl_context.mdl_savepoint();
 
+  /*
+    Set variables specified by
+      SET STATEMENT var1=value1 [, var2=value2, ...] FOR <statement>
+    clause for duration of prepare phase. Original values of variable
+    listed in the SET STATEMENT clause is restored right after return
+    from the function check_prepared_statement()
+  */
+  if (likely(error == 0))
+    error= run_set_statement_if_requested(thd, lex);
+
   /* 
    The only case where we should have items in the thd->free_list is
    after stmt->set_params_from_vars(), which may in some cases create
@@ -4278,6 +4288,12 @@ bool Prepared_statement::prepare(const char *packet, uint packet_len)
     lex->context_analysis_only&= ~CONTEXT_ANALYSIS_ONLY_PREPARE;
   }
 
+  /*
+    Restore original values of variables modified on handling
+    SET STATEMENT clause.
+  */
+  thd->lex->restore_set_statement_var();
+
   /* The order is important */
   lex->unit.cleanup();
 
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 2f88d4f9217..5443d60efe0 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -1,5 +1,5 @@
 /* Copyright (c) 2000, 2016, Oracle and/or its affiliates.
-   Copyright (c) 2009, 2020, MariaDB Corporation.
+   Copyright (c) 2009, 2021, MariaDB Corporation.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -4682,6 +4682,9 @@ mysql_select(THD *thd, TABLE_LIST *tables, List<Item> &fields, COND *conds,
   }
   else
   {
+    if (thd->lex->describe)
+      select_options|= SELECT_DESCRIBE;
+
     /*
       When in EXPLAIN, delay deleting the joins so that they are still
       available when we're producing EXPLAIN EXTENDED warning text.
@@ -14499,22 +14502,71 @@ return_zero_rows(JOIN *join, select_result *result, List<TABLE_LIST> &tables,
   DBUG_RETURN(0);
 }
 
-/*
-  used only in JOIN::clear
+/**
+  used only in JOIN::clear (always) and in do_select()
+  (if there where no matching rows)
+
+  @param join            JOIN
+  @param cleared_tables  If not null, clear also const tables and mark all
+                         cleared tables in the map. cleared_tables is only
+                         set when called from do_select() when there is a
+                         group function and there where no matching rows.
 */
-static void clear_tables(JOIN *join)
+
+static void clear_tables(JOIN *join, table_map *cleared_tables)
 {
   /* 
-    must clear only the non-const tables, as const tables
-    are not re-calculated.
+    must clear only the non-const tables as const tables are not re-calculated.
   */
   for (uint i= 0 ; i < join->table_count ; i++)
   {
-    if (!(join->table[i]->map & join->const_table_map))
-      mark_as_null_row(join->table[i]);		// All fields are NULL
+    TABLE *table= join->table[i];
+
+    if (table->null_row)
+      continue;                                 // Nothing more to do
+    if (!(table->map & join->const_table_map) || cleared_tables)
+    {
+      if (cleared_tables)
+      {
+        (*cleared_tables)|= (((table_map) 1) << i);
+        if (table->s->null_bytes)
+        {
+          /*
+            Remember null bits for the record so that we can restore the
+            original const record in unclear_tables()
+          */
+          memcpy(table->record[1], table->null_flags, table->s->null_bytes);
+        }
+      }
+      mark_as_null_row(table);                  // All fields are NULL
+    }
+  }
+}
+
+
+/**
+   Reverse null marking for tables and restore null bits.
+
+   We have to do this because the tables may be re-used in a sub query
+   and the subquery will assume that the const tables contains the original
+   data before clear_tables().
+*/
+
+static void unclear_tables(JOIN *join, table_map *cleared_tables)
+{
+  for (uint i= 0 ; i < join->table_count ; i++)
+  {
+    if ((*cleared_tables) & (((table_map) 1) << i))
+    {
+      TABLE *table= join->table[i];
+      if (table->s->null_bytes)
+        memcpy(table->null_flags, table->record[1], table->s->null_bytes);
+      unmark_as_null_row(table);
+    }
   }
 }
 
+
 /*****************************************************************************
   Make som simple condition optimization:
   If there is a test 'field = const' change all refs to 'field' to 'const'
@@ -17985,17 +18037,34 @@ Field *Item_field::create_tmp_field_ex(MEM_ROOT *root, TABLE *table,
   src->set_field(field);
   if (!(result= create_tmp_field_from_item_field(root, table, NULL, param)))
     return NULL;
-  /*
-    Fields that are used as arguments to the DEFAULT() function already have
-    their data pointers set to the default value during name resolution. See
-    Item_default_value::fix_fields.
-  */
-  if (type() != Item::DEFAULT_VALUE_ITEM && field->eq_def(result))
+  if (field->eq_def(result))
     src->set_default_field(field);
   return result;
 }
 
 
+Field *Item_default_value::create_tmp_field_ex(MEM_ROOT *root, TABLE *table,
+                                               Tmp_field_src *src,
+                                               const Tmp_field_param *param)
+{
+  if (field->default_value && (field->flags & BLOB_FLAG))
+  {
+    /*
+      We have to use a copy function when using a blob with default value
+      as the we have to calculate the default value before we can use it.
+    */
+     get_tmp_field_src(src, param);
+     return tmp_table_field_from_field_type(root, table);
+  }
+  /*
+    Same code as in Item_field::create_tmp_field_ex, except no default field
+    handling
+  */
+  src->set_field(field);
+  return create_tmp_field_from_item_field(root, table, nullptr, param);
+}
+
+
 Field *Item_ref::create_tmp_field_ex(MEM_ROOT *root, TABLE *table,
                                      Tmp_field_src *src,
                                      const Tmp_field_param *param)
@@ -18097,7 +18166,13 @@ Field *Item_func_sp::create_tmp_field_ex(MEM_ROOT *root, TABLE *table,
                        the record in the original table.
                        If modify_item is 0 then fill_record() will update
                        the temporary table
-
+  @param table_cant_handle_bit_fields
+                       Set to 1 if the temporary table cannot handle bit
+                       fields. Only set for heap tables when the bit field
+                       is part of an index.
+  @param make_copy_field
+                       Set when using with rollup when we want to have
+                       an exact copy of the field.
   @retval
     0                  on error
   @retval
@@ -20162,6 +20237,7 @@ do_select(JOIN *join, Procedure *procedure)
   if (join->only_const_tables() && !join->need_tmp)
   {
     Next_select_func end_select= setup_end_select_func(join, NULL);
+
     /*
       HAVING will be checked after processing aggregate functions,
       But WHERE should checked here (we alredy have read tables).
@@ -20188,6 +20264,17 @@ do_select(JOIN *join, Procedure *procedure)
     }
     else if (join->send_row_on_empty_set())
     {
+      table_map cleared_tables= (table_map) 0;
+      if (end_select == end_send_group)
+      {
+        /*
+          Was a grouping query but we did not find any rows. In this case
+          we clear all tables to get null in any referenced fields,
+          like in case of:
+          SELECT MAX(a) AS f1, a AS f2 FROM t1 WHERE VALUE(a) IS NOT NULL
+        */
+        clear_tables(join, &cleared_tables);
+      }
       if (!join->having || join->having->val_int())
       {
         List<Item> *columns_list= (procedure ? &join->procedure_fields_list :
@@ -20195,6 +20282,12 @@ do_select(JOIN *join, Procedure *procedure)
         rc= join->result->send_data_with_check(*columns_list,
                                                join->unit, 0) > 0;
       }
+      /*
+        We have to remove the null markings from the tables as this table
+        may be part of a sub query that is re-evaluated
+      */
+      if (cleared_tables)
+        unclear_tables(join, &cleared_tables);
     }
     /*
       An error can happen when evaluating the conds 
@@ -21175,8 +21268,8 @@ join_read_const_table(THD *thd, JOIN_TAB *tab, POSITION *pos)
     if ((table->null_row= MY_TEST((*tab->on_expr_ref)->val_int() == 0)))
       mark_as_null_row(table);  
   }
-  if (!table->null_row)
-    table->maybe_null=0;
+  if (!table->null_row && ! tab->join->mixed_implicit_grouping)
+    table->maybe_null= 0;
 
   {
     JOIN *join= tab->join;
@@ -26334,7 +26427,7 @@ int JOIN::rollup_write_data(uint idx, TMP_TABLE_PARAM *tmp_table_param_arg, TABL
 
 void JOIN::clear()
 {
-  clear_tables(this);
+  clear_tables(this, 0);
   copy_fields(&tmp_table_param);
 
   if (sum_funcs)
diff --git a/sql/sql_truncate.cc b/sql/sql_truncate.cc
index 2bf99993a50..e699869d644 100644
--- a/sql/sql_truncate.cc
+++ b/sql/sql_truncate.cc
@@ -477,6 +477,15 @@ bool Sql_cmd_truncate_table::truncate_table(THD *thd, TABLE_LIST *table_ref)
       */
       error= handler_truncate(thd, table_ref, FALSE);
 
+      if (error == TRUNCATE_OK && thd->locked_tables_mode &&
+          (table_ref->table->file->ht->flags &
+           HTON_REQUIRES_CLOSE_AFTER_TRUNCATE))
+      {
+        thd->locked_tables_list.mark_table_for_reopen(thd, table_ref->table);
+        if (unlikely(thd->locked_tables_list.reopen_tables(thd, true)))
+          thd->locked_tables_list.unlink_all_closed_tables(thd, NULL, 0);
+      }
+
       /*
         All effects of a TRUNCATE TABLE operation are committed even if
         truncation fails in the case of non transactional tables. Thus, the
diff --git a/sql/sql_tvc.cc b/sql/sql_tvc.cc
index b9bdd04eede..c48e40ad53a 100644
--- a/sql/sql_tvc.cc
+++ b/sql/sql_tvc.cc
@@ -679,7 +679,7 @@ st_select_lex *wrap_tvc(THD *thd, st_select_lex *tvc_sl,
                         st_select_lex *parent_select)
 {
   LEX *lex= thd->lex;
-  select_result *save_result= thd->lex->result;
+  select_result *save_result= lex->result;
   uint8 save_derived_tables= lex->derived_tables;
   thd->lex->result= NULL;
 
@@ -760,13 +760,13 @@ st_select_lex *wrap_tvc(THD *thd, st_select_lex *tvc_sl,
 
   if (arena)
     thd->restore_active_arena(arena, &backup);
-  thd->lex->result= save_result;
+  lex->result= save_result;
   return wrapper_sl;
 
 err:
   if (arena)
     thd->restore_active_arena(arena, &backup);
-  thd->lex->result= save_result;
+  lex->result= save_result;
   lex->derived_tables= save_derived_tables;
   return 0;
 }
@@ -851,14 +851,9 @@ Item_subselect::wrap_tvc_into_select(THD *thd, st_select_lex *tvc_sl)
   {
     if (engine->engine_type() == subselect_engine::SINGLE_SELECT_ENGINE)
       ((subselect_single_select_engine *) engine)->change_select(wrapper_sl);
-    lex->current_select= wrapper_sl;
-    return wrapper_sl;
-  }
-  else
-  {
-    lex->current_select= parent_select;
-    return 0;
   }
+  lex->current_select= parent_select;
+  return wrapper_sl;
 }
 
 
diff --git a/sql/table.h b/sql/table.h
index 9eefd915844..58789dc3826 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -3202,6 +3202,12 @@ inline void mark_as_null_row(TABLE *table)
     bfill(table->null_flags,table->s->null_bytes,255);
 }
 
+inline void unmark_as_null_row(TABLE *table)
+{
+  table->null_row=0;
+  table->status= STATUS_NO_RECORD;
+}
+
 bool is_simple_order(ORDER *order);
 
 class Open_tables_backup;