Merge

Docs/manual.texi:
  SCCS merged

Docs/manual.texi

@@ -46929,6 +46929,10 @@ not yet 100% confident in this code.
 @appendixsubsec Changes in release 3.23.53
 @itemize @bullet
 @item
+Changed @code{AND/OR} to report that they can return NULL. This fixes a
+small problem in @code{GROUP BY} on @code{AND/OR} expression that return
+@code{NULL}.
+@item
 Fixed a bug that @code{OPTIMIZE} of locked and modified MyISAM table,
 reported table corruption.
 @item

mysql-test/r/distinct.result

@@ -69,7 +69,8 @@ a	max(id)	b
 0	0	
 NULL	NULL	NULL
 grp	count(*)
-0	7
+NULL	1
+0	6
 1	6
 FACILITY
 NULL

sql/item_cmpfunc.cc

@@ -1097,6 +1097,8 @@ Item_cond::fix_fields(THD *thd,TABLE_LIST *tables)
     used_tables_cache|=item->used_tables();
     with_sum_func= with_sum_func || item->with_sum_func;
     const_item_cache&=item->const_item();
+    if (item->maybe_null)
+      maybe_null=1;
   }
   if (thd)
     thd->cond_count+=list.elements;

sql/mysql_priv.h

@@ -447,6 +447,7 @@ bool rm_temporary_table(enum db_type base, char *path);
 bool send_fields(THD *thd,List<Item> &item,uint send_field_count);
 void free_io_cache(TABLE *entry);
 void intern_close_table(TABLE *entry);
+bool close_thread_table(THD *thd, TABLE **table_ptr);
 void close_thread_tables(THD *thd,bool locked=0);
 void close_temporary_tables(THD *thd);
 TABLE **find_temporary_table(THD *thd, const char *db, const char *table_name);

sql/sql_base.cc

@@ -428,7 +428,6 @@ void close_thread_tables(THD *thd, bool locked)
     DBUG_VOID_RETURN;				// LOCK TABLES in use
   }
 
-  TABLE *table,*next;
   bool found_old_table=0;
 
   if (thd->lock)
@@ -441,41 +440,10 @@ void close_thread_tables(THD *thd, bool locked)
 
   DBUG_PRINT("info", ("thd->open_tables=%p", thd->open_tables));
 
-  for (table=thd->open_tables ; table ; table=next)
+  while (thd->open_tables)
-  {
+    found_old_table|=close_thread_table(thd, &thd->open_tables);
-    next=table->next;
-    if (table->version != refresh_version ||
-	thd->version != refresh_version || !table->db_stat)
-    {
-      VOID(hash_delete(&open_cache,(byte*) table));
-      found_old_table=1;
-    }
-    else
-    {
-      if (table->flush_version != flush_version)
-      {
-	table->flush_version=flush_version;
-	table->file->extra(HA_EXTRA_FLUSH);
-      }
-      else
-      {
-	// Free memory and reset for next loop
-	table->file->extra(HA_EXTRA_RESET);
-      }
-      table->in_use=0;
-      if (unused_tables)
-      {
-	table->next=unused_tables;		/* Link in last */
-	table->prev=unused_tables->prev;
-	unused_tables->prev=table;
-	table->prev->next=table;
-      }
-      else
-	unused_tables=table->next=table->prev=table;
-    }
-  }
   thd->some_tables_deleted=0;
-  thd->open_tables=0;
+
   /* Free tables to hold down open files */
   while (open_cache.records > table_cache_size && unused_tables)
     VOID(hash_delete(&open_cache,(byte*) unused_tables)); /* purecov: tested */
@@ -491,6 +459,48 @@ void close_thread_tables(THD *thd, bool locked)
   DBUG_VOID_RETURN;
 }
 
+/* move one table to free list */
+
+bool close_thread_table(THD *thd, TABLE **table_ptr)
+{
+  DBUG_ENTER("close_thread_table");
+
+  bool found_old_table=0;
+  TABLE *table=*table_ptr;
+
+  *table_ptr=table->next;
+  if (table->version != refresh_version ||
+      thd->version != refresh_version || !table->db_stat)
+  {
+    VOID(hash_delete(&open_cache,(byte*) table));
+    found_old_table=1;
+  }
+  else
+  {
+    if (table->flush_version != flush_version)
+    {
+      table->flush_version=flush_version;
+      table->file->extra(HA_EXTRA_FLUSH);
+    }
+    else
+    {
+      // Free memory and reset for next loop
+      table->file->extra(HA_EXTRA_RESET);
+    }
+    table->in_use=0;
+    if (unused_tables)
+    {
+      table->next=unused_tables;		/* Link in last */
+      table->prev=unused_tables->prev;
+      unused_tables->prev=table;
+      table->prev->next=table;
+    }
+    else
+      unused_tables=table->next=table->prev=table;
+  }
+  DBUG_RETURN(found_old_table);
+}
+
 	/* Close and delete temporary tables */
 
 void close_temporary(TABLE *table,bool delete_table)

sql/sql_table.cc

@@ -19,6 +19,9 @@
 
 #include "mysql_priv.h"
 #include <hash.h>
+#ifdef HAVE_BERKELEY_DB
+#include <ha_berkeley.h>
+#endif
 #include <myisam.h>
 
 #ifdef __WIN__
@@ -1675,11 +1678,18 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   VOID(pthread_cond_broadcast(&COND_refresh));
   VOID(pthread_mutex_unlock(&LOCK_open));
 #ifdef HAVE_BERKELEY_DB
-  extern bool berkeley_flush_logs(void);
   if (old_db_type == DB_TYPE_BERKELEY_DB)
   {
-    (void)berkeley_flush_logs();
+    (void) berkeley_flush_logs();
-    table=open_ltable(thd,table_list,TL_READ);
+    /*
+      For the alter table to be properly flushed to the logs, we
+      have to open the new table.  If not, we get a problem on server
+      shutdown.
+    */
+    if (!open_tables(thd, table_list))		// Should always succeed
+    {
+      close_thread_table(thd, &table_list->table);
+    }
   }
 #endif