new lock for multiupdate:

- open and create derived tables
- detect which tables should be locked for write
- lock and fill derived tables
some unitialized variables fixed


mysql-test/r/lock_multi.result:
  correct results returned
mysql-test/r/multi_update.result:
  correct results returned
mysql-test/r/view.result:
  correct results returned
mysql-test/t/multi_update.test:
  correct results returned
mysql-test/t/view.test:
  correct results returned
sql/mysql_priv.h:
  derived tables processing splited on table creation and table filling
sql/sql_base.cc:
  derived tables processing splited on table creation and table filling
sql/sql_class.h:
  function to detect when we need fill derived tables
sql/sql_derived.cc:
  derived tables processing splited on table creation and table filling
sql/sql_lex.cc:
  fixed uninitialized value
sql/sql_load.cc:
  fixed uninitialized value
sql/sql_parse.cc:
  initialization muved (will be done for all queries)
sql/sql_prepare.cc:
  preparation of multiupdate changed a bit because new locking procedure
sql/sql_update.cc:
  new lock for multiupdate:
  - open and create derived tables
  - detect which tables should be locked for write
  - lock and fill derived tables
sql/table.h:
  place to store select_result between creation and filling tables

1 files changed, 135 insertions, 101 deletions

diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index 0923cf811f5..10ef6a081b6 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -25,15 +25,15 @@
 #include "sql_select.h"
 #include "sql_acl.h"
 
-static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *s,
-			 TABLE_LIST *t);
+
 
 /*
-  Resolve derived tables in all queries
+  call given derived table processor (preparing or filling tables)
 
   SYNOPSIS
     mysql_handle_derived()
     lex                 LEX for this thread
+    processor           procedure of derived table processing
 
   RETURN
     0	ok
@@ -42,7 +42,7 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *s,
 */
 
 int
-mysql_handle_derived(LEX *lex)
+mysql_handle_derived(LEX *lex, int (*processor)(THD*, LEX*, TABLE_LIST*))
 {
   if (lex->derived_tables)
   {
@@ -55,14 +55,8 @@ mysql_handle_derived(LEX *lex)
 	   cursor= cursor->next_local)
       {
 	int res;
-	if (cursor->derived && (res= mysql_derived(lex->thd, lex,
-						   cursor->derived,
-						   cursor)))
-	{
+	if ((res= (*processor)(lex->thd, lex, cursor)))
 	  return res;
-	}
-	else if (cursor->ancestor)
-	  cursor->set_ancestor();
       }
       if (lex->describe)
       {
@@ -80,20 +74,16 @@ mysql_handle_derived(LEX *lex)
 
 
 /*
-  Resolve derived tables in all queries
+  Create temporary table structure (but do not fill it)
 
   SYNOPSIS
     mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit, TABLE_LIST *t)
     thd			Thread handle
     lex                 LEX for this thread
-    unit                node that contains all SELECT's for derived tables
-    t                   TABLE_LIST for the upper SELECT
+    orig_table_list     TABLE_LIST for the upper SELECT
 
   IMPLEMENTATION
-    Derived table is resolved with temporary table. It is created based on the
-    queries defined. After temporary table is created, if this is not EXPLAIN,
-    then the entire unit / node is deleted. unit is deleted if UNION is used 
-    for derived table and node is deleted is it is a  simple SELECT.
+    Derived table is resolved with temporary table.
 
     After table creation, the above TABLE_LIST is updated with a new table.
 
@@ -107,60 +97,126 @@ mysql_handle_derived(LEX *lex)
     0	ok
     1	Error
     -1	Error and error message given
-*/  
-
+  */
 
-static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
-			 TABLE_LIST *org_table_list)
+int mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *orig_table_list)
 {
-  SELECT_LEX *first_select= unit->first_select();
-  TABLE *table;
-  int res;
-  select_union *derived_result;
-  bool is_union= first_select->next_select() && 
-    first_select->next_select()->linkage == UNION_TYPE;
-  SELECT_LEX *save_current_select= lex->current_select;
-  DBUG_ENTER("mysql_derived");
-
-  if (!(derived_result= new select_union(0)))
-    DBUG_RETURN(1); // out of memory
-
-  // st_select_lex_unit::prepare correctly work for single select
-  if ((res= unit->prepare(thd, derived_result, 0)))
-    goto exit;
-
-	
-  derived_result->tmp_table_param.init();
-  derived_result->tmp_table_param.field_count= unit->types.elements;
-  /*
-    Temp table is created so that it hounours if UNION without ALL is to be 
-    processed
-  */
-  if (!(table= create_tmp_table(thd, &derived_result->tmp_table_param,
-				unit->types, (ORDER*) 0, 
-				is_union && unit->union_distinct, 1,
-				(first_select->options | thd->options |
-				 TMP_TABLE_ALL_COLUMNS),
-				HA_POS_ERROR,
-				org_table_list->alias)))
+  SELECT_LEX_UNIT *unit= orig_table_list->derived;
+  int res= 0;
+  if (unit)
   {
-    res= -1;
-    goto exit;
+    SELECT_LEX *first_select= unit->first_select();
+    TABLE *table= 0;
+    select_union *derived_result;
+    bool is_union= first_select->next_select() && 
+      first_select->next_select()->linkage == UNION_TYPE;
+    DBUG_ENTER("mysql_derived");
+
+    if (!(derived_result= new select_union(0)))
+      DBUG_RETURN(1); // out of memory
+
+    // st_select_lex_unit::prepare correctly work for single select
+    if ((res= unit->prepare(thd, derived_result, 0)))
+      goto exit;
+
+
+    derived_result->tmp_table_param.init();
+    derived_result->tmp_table_param.field_count= unit->types.elements;
+    /*
+      Temp table is created so that it hounours if UNION without ALL is to be 
+      processed
+    */
+    if (!(table= create_tmp_table(thd, &derived_result->tmp_table_param,
+				  unit->types, (ORDER*) 0,
+				  is_union && unit->union_distinct, 1,
+				  (first_select->options | thd->options |
+				   TMP_TABLE_ALL_COLUMNS),
+				  HA_POS_ERROR,
+				  orig_table_list->alias)))
+    {
+      res= -1;
+      goto exit;
+    }
+    derived_result->set_table(table);
+
+exit:
+    /*
+      if it is preparation PS only or commands that need only VIEW structure
+      then we do not need real data and we can skip execution (and parameters
+      is not defined, too)
+    */
+    if (res)
+    {
+      if (table)
+	free_tmp_table(thd, table);
+      delete derived_result;
+    }
+    else
+    {
+      if (!thd->fill_derived_tables())
+	delete derived_result;
+      orig_table_list->derived_result= derived_result;
+      orig_table_list->table= table;
+      orig_table_list->real_name= table->real_name;
+      table->derived_select_number= first_select->select_number;
+      table->tmp_table= TMP_TABLE;
+#ifndef NO_EMBEDDED_ACCESS_CHECKS
+      table->grant.privilege= SELECT_ACL;
+#endif
+      orig_table_list->db= (char *)"";
+      // Force read of table stats in the optimizer
+      table->file->info(HA_STATUS_VARIABLE);
+      /* Add new temporary table to list of open derived tables */
+      table->next= thd->derived_tables;
+      thd->derived_tables= table;
+    }
   }
-  derived_result->set_table(table);
+  else if (orig_table_list->ancestor)
+    orig_table_list->set_ancestor();
+  return (res);
+}
+
 
-  /*
-    if it is preparation PS only or commands that need only VIEW structure
-    then we do not need real data and we can skip execution (and parameters
-    is not defined, too)
+/*
+  fill derived table
+
+  SYNOPSIS
+    mysql_derived_filling()
+    thd			Thread handle
+    lex                 LEX for this thread
+    unit                node that contains all SELECT's for derived tables
+    orig_table_list     TABLE_LIST for the upper SELECT
+
+  IMPLEMENTATION
+    Derived table is resolved with temporary table. It is created based on the
+    queries defined. After temporary table is filled, if this is not EXPLAIN,
+    then the entire unit / node is deleted. unit is deleted if UNION is used
+    for derived table and node is deleted is it is a  simple SELECT.
+
+  RETURN
+    0	ok
+    1	Error
+    -1	Error and error message given
   */
-  if (!thd->only_prepare() && !lex->only_view_structure())
+
+int mysql_derived_filling(THD *thd, LEX *lex, TABLE_LIST *orig_table_list)
+{
+  TABLE *table= orig_table_list->table;
+  SELECT_LEX_UNIT *unit= orig_table_list->derived;
+  int res= 0;
+
+  /*check that table creation pass without problem and it is derived table */
+  if (table && unit)
   {
+    SELECT_LEX *first_select= unit->first_select();
+    select_union *derived_result= orig_table_list->derived_result;
+    SELECT_LEX *save_current_select= lex->current_select;
+    bool is_union= first_select->next_select() &&
+      first_select->next_select()->linkage == UNION_TYPE;
     if (is_union)
     {
       // execute union without clean up
-      if (!(res= unit->prepare(thd, derived_result, SELECT_NO_UNLOCK)))
-	res= unit->exec();
+      res= unit->exec();
     }
     else
     {
@@ -173,7 +229,7 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
 	first_select->options&= ~OPTION_FOUND_ROWS;
 
       lex->current_select= first_select;
-      res= mysql_select(thd, &first_select->ref_pointer_array, 
+      res= mysql_select(thd, &first_select->ref_pointer_array,
 			(TABLE_LIST*) first_select->table_list.first,
 			first_select->with_wild,
 			first_select->item_list, first_select->where,
@@ -186,49 +242,27 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
 			 SELECT_NO_UNLOCK),
 			derived_result, unit, first_select);
     }
-  }
 
-  if (!res)
-  {
-    /*
-      Here we entirely fix both TABLE_LIST and list of SELECT's as
-      there were no derived tables
-    */
-    if (derived_result->flush())
-      res= 1;
-    else
+    if (!res)
     {
-      org_table_list->real_name= table->real_name;
-      org_table_list->table= table;
-      table->derived_select_number= first_select->select_number;
-      table->tmp_table= TMP_TABLE;
-#ifndef NO_EMBEDDED_ACCESS_CHECKS
-      table->grant.privilege= SELECT_ACL;
-#endif
-      org_table_list->db= (char *)"";
-      // Force read of table stats in the optimizer
-      table->file->info(HA_STATUS_VARIABLE);
-    }
+      /*
+        Here we entirely fix both TABLE_LIST and list of SELECT's as
+        there were no derived tables
+      */
+      if (derived_result->flush())
+        res= 1;
 
-    if (!lex->describe)
-      unit->cleanup();
-    if (res)
-      free_tmp_table(thd, table);
+      if (!lex->describe)
+        unit->cleanup();
+    }
     else
     {
-      /* Add new temporary table to list of open derived tables */
-      table->next= thd->derived_tables;
-      thd->derived_tables= table;
+      free_tmp_table(thd, table);
+      unit->cleanup();
     }
+    lex->current_select= save_current_select;
+    if (res)
+      free_tmp_table(thd, table);
   }
-  else
-  {
-    free_tmp_table(thd, table);
-    unit->cleanup();
-  }
-
-exit:
-  delete derived_result;
-  lex->current_select= save_current_select;
-  DBUG_RETURN(res);
+  return res;
 }