Bug#20030284 - HANDLE_FATAL_SIGNAL (SIG=11) IN NAME_HASH_SEARCH

Follow up patch to backport patch committed in 5.8 to 5.7.

Author: phulakun

sql/sql_base.cc

@@ -1596,6 +1596,11 @@ void close_thread_tables(THD *thd)
     for (table= thd->derived_tables ; table ; table= next)
     {
       next= table->next;
+
+      // Restore original name of materialized table
+      if (!table->pos_in_table_list->schema_table)
+        table->pos_in_table_list->reset_name_temporary();
+
       free_tmp_table(thd, table);
     }
     thd->derived_tables= 0;
@@ -4804,25 +4809,6 @@ open_and_process_table(THD *thd, LEX *lex, TABLE_LIST *tables,
   if (tables->is_derived())
     goto end;
 
-  if (tables->is_view())
-  {
-    /*
-      We restore view's name and database possibly wiped out by derived tables
-      processing and fall back to standard open process in order to
-      obtain proper metadata locks and do other necessary steps like
-      stored routine processing.
-    */
-    if (tables->db != tables->view_db.str)
-    {
-      tables->db= tables->view_db.str;
-      tables->db_length= tables->view_db.length;
-    }
-    if (tables->table_name != tables->view_name.str)
-    {
-      tables->table_name= tables->view_name.str;
-      tables->table_name_length= tables->view_name.length;
-    }
-  }
   /*
     If this TABLE_LIST object is a placeholder for an information_schema
     table, create a temporary table to represent the information_schema

sql/sql_derived.cc

@@ -126,15 +126,10 @@ bool TABLE_LIST::setup_materialized_derived(THD *thd)
     DBUG_RETURN(true);        /* purecov: inspected */
 
   table= derived_result->table;
-
-  table_name= table->s->table_name.str;
-  table_name_length= table->s->table_name.length;
-
   table->pos_in_table_list= this;
 
-  // Erasing the database name is needed for alignment with temp. table
-  db= (char *)"";
-  db_length= 0;
+  // Make table's name same as the underlying materialized table
+  set_name_temporary();
 
   table->s->tmp_table= NON_TRANSACTIONAL_TMP_TABLE;
 #ifndef NO_EMBEDDED_ACCESS_CHECKS

sql/table.cc

@@ -6456,28 +6456,11 @@ void TABLE_LIST::reinit_before_use(THD *thd)
   table= 0;
 
   /*
-   Reset table_name and table_name_length,if it is a anonymous derived table
-   or schema table. They are not valid as TABLEs were closed in the end of
-   previous prepare or execute call. For derived table of view, restore view's
-   name and database wiped out by derived table processing.
-
- */
-  if (is_view_or_derived())
-  {
-    if (is_view())
-    {
-      db= view_db.str;
-      db_length= view_db.length;
-      table_name= view_name.str;
-      table_name_length= view_name.length;
-    }
-    else
-    {
-      table_name= NULL;
-      table_name_length= 0;
-    }
-  }
-  else if (schema_table_name)
+    Reset table_name and table_name_length for schema table.
+    They are not valid as TABLEs were closed in the end of previous prepare
+    or execute call.
+  */
+  if (schema_table_name)
   {
     table_name= schema_table_name;
     table_name_length= strlen(schema_table_name);

sql/table.h

@@ -1912,6 +1912,30 @@ struct TABLE_LIST
     return derived;
   }
 
+  /// Set temporary name from underlying temporary table:
+  void set_name_temporary()
+  {
+    DBUG_ASSERT(is_view_or_derived() && uses_materialization());
+    table_name= table->s->table_name.str;
+    table_name_length= table->s->table_name.length;
+    db= (char *)"";
+    db_length= 0;
+  }
+
+  /// Reset original name for temporary table.
+  void reset_name_temporary()
+  {
+    DBUG_ASSERT(is_view_or_derived() && uses_materialization());
+    DBUG_ASSERT(db != view_db.str && table_name != view_name.str);
+    if (is_view())
+    {
+      db= view_db.str;
+      db_length= view_db.length;
+    }
+    table_name= view_name.str;
+    table_name_length= view_name.length;
+  }
+
   /// Resolve a derived table or view reference
   bool resolve_derived(THD *thd, bool apply_semijoin);