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More code cleanups

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This commit is contained in:
Sergey Petrunya
2009-08-19 01:19:48 +03:00
parent 1396c2d2fa
commit eed5a47c34
1 changed files with 50 additions and 91 deletions
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141
sql/opt_table_elimination.cc
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@@ -295,14 +295,16 @@ public:
bzero(table_deps, sizeof(table_deps));
}
JOIN *join;
JOIN *join; /* Join we're working on */
/* Array of equality dependencies */
Equality_module *equality_deps;
uint n_equality_deps; /* Number of elements in the array */
/* tablenr -> Table_value* mapping. */
Table_value *table_deps[MAX_KEY];
/* Element for the outer join we're attempting to eliminate */
Outer_join_module *outer_join_dep;
/* Bitmap of how expressions depend on bits */
@@ -312,13 +314,13 @@ public:
void eliminate_tables(JOIN *join);
static bool
eliminate_tables_for_list(Table_elimination *te,
eliminate_tables_for_list(JOIN *join,
List<TABLE_LIST> *join_list,
table_map tables_in_list,
Item *on_expr,
table_map tables_used_elsewhere);
static
bool check_func_dependency(Table_elimination *te,
bool check_func_dependency(JOIN *join,
table_map dep_tables,
List_iterator<TABLE_LIST> *it,
TABLE_LIST *oj_tbl,
@@ -752,61 +754,6 @@ static Field_value *get_field_value(Table_elimination *te, Field *field)
}
/*
Create an Outer_join_module object for the given outer join
DESCRIPTION
Outer_join_module objects for children (or further descendants) are always
created before the parents.
*/
#if 0
static
Outer_join_module *get_outer_join_dep(Table_elimination *te,
// TABLE_LIST *outer_join,
table_map deps_map)
{
Outer_join_module *oj_dep;
if (!(oj_dep= new Outer_join_module(/*outer_join, */my_count_bits(deps_map))))
return NULL;
/*
Collect a bitmap fo tables that we depend on, and also set parent pointer
for descendant outer join elements.
*/
Table_map_iterator it(deps_map);
int idx;
while ((idx= it.next_bit()) != Table_map_iterator::BITMAP_END)
{
Table_value *table_dep;
if (!(table_dep= te->table_deps[idx]))
{
/*
We get here only when ON expression had no references to inner tables
and Table_map objects weren't created for them. This is a rare/
unimportant case so it's ok to do not too efficient searches.
*/
TABLE *table= NULL;
for (TABLE_LIST *tlist= te->join->select_lex->leaf_tables; tlist;
tlist=tlist->next_leaf)
{
if (tlist->table->tablenr == (uint)idx)
{
table=tlist->table;
break;
}
}
DBUG_ASSERT(table);
if (!(table_dep= get_table_value(te, table)))
return NULL;
}
table_dep->outer_join_dep= oj_dep;
}
return oj_dep;
}
#endif
/*
This is used to analyze expressions in "tbl.col=expr" dependencies so
that we can figure out which fields the expression depends on.
@@ -852,33 +799,39 @@ public:
/*
Setup equality dependencies
Setup inbound dependency relationships for tbl.col=expr equalities
SYNOPSIS
setup_equality_deps()
setup_equality_modules_deps()
te Table elimination context
bound_deps_list OUT Start of linked list of elements that were found to
be bound (caller will use this to see if that
allows to declare further elements bound)
DESCRIPTION
RETURN
Setup inbound dependency relationships for tbl.col=expr equalities:
- allocate a bitmap where we store such dependencies
- for each "tbl.col=expr" equality, analyze the expr part and find out
which fields it refers to and set appropriate dependencies.
RETURN
FALSE OK
TRUE Out of memory
*/
static
bool setup_equality_deps(Table_elimination *te, Module_dep **bound_deps_list)
bool setup_equality_modules_deps(Table_elimination *te,
Module_dep **bound_deps_list)
{
DBUG_ENTER("setup_equality_deps");
DBUG_ENTER("setup_equality_modules_deps");
if (!te->n_equality_deps)
DBUG_RETURN(TRUE);
/*
Count Field_value objects and assign each of them a unique bitmap_offset.
Count Field_value objects and assign each of them a unique bitmap_offset
value.
*/
uint offset= 0;
for (Table_value **tbl_dep=te->table_deps;
tbl_dep < te->table_deps + MAX_TABLES;
tbl_dep++) // psergey-todo: Wipe this out altogether
tbl_dep++)
{
if (*tbl_dep)
{
@@ -924,7 +877,6 @@ bool setup_equality_deps(Table_elimination *te, Module_dep **bound_deps_list)
}
*bound_deps_list= bound_dep;
DBUG_EXECUTE("test", dbug_print_deps(te); );
DBUG_RETURN(FALSE);
}
@@ -1016,15 +968,7 @@ void eliminate_tables(JOIN *join)
if (all_tables & ~used_tables)
{
/* There are some tables that we probably could eliminate. Try it. */
//psergey-todo: move allocs to somewhere else.
Table_elimination te(join);
uint m= max(thd->lex->current_select->max_equal_elems,1);
uint max_elems= ((thd->lex->current_select->cond_count+1)*2 +
thd->lex->current_select->between_count)*m + 1 + 10;
if (!(te.equality_deps= new Equality_module[max_elems]))
DBUG_VOID_RETURN;
eliminate_tables_for_list(&te, join->join_list, all_tables, NULL,
eliminate_tables_for_list(join, join->join_list, all_tables, NULL,
used_tables);
}
DBUG_VOID_RETURN;
@@ -1056,7 +1000,7 @@ void eliminate_tables(JOIN *join)
*/
static bool
eliminate_tables_for_list(Table_elimination *te, List<TABLE_LIST> *join_list,
eliminate_tables_for_list(JOIN *join, List<TABLE_LIST> *join_list,
table_map list_tables, Item *on_expr,
table_map tables_used_elsewhere)
{
@@ -1074,13 +1018,13 @@ eliminate_tables_for_list(Table_elimination *te, List<TABLE_LIST> *join_list,
if (tbl->nested_join)
{
/* This is "... LEFT JOIN (join_nest) ON cond" */
if (eliminate_tables_for_list(te,
if (eliminate_tables_for_list(join,
&tbl->nested_join->join_list,
tbl->nested_join->used_tables,
tbl->on_expr,
outside_used_tables))
{
mark_as_eliminated(te->join, tbl);
mark_as_eliminated(join, tbl);
}
else
all_eliminated= FALSE;
@@ -1089,10 +1033,10 @@ eliminate_tables_for_list(Table_elimination *te, List<TABLE_LIST> *join_list,
{
/* This is "... LEFT JOIN tbl ON cond" */
if (!(tbl->table->map & outside_used_tables) &&
check_func_dependency(te, tbl->table->map, NULL, tbl,
check_func_dependency(join, tbl->table->map, NULL, tbl,
tbl->on_expr))
{
mark_as_eliminated(te->join, tbl);
mark_as_eliminated(join, tbl);
}
else
all_eliminated= FALSE;
@@ -1109,7 +1053,7 @@ eliminate_tables_for_list(Table_elimination *te, List<TABLE_LIST> *join_list,
if (all_eliminated && on_expr && !(list_tables & tables_used_elsewhere))
{
it.rewind();
return check_func_dependency(te, list_tables & ~te->join->eliminated_tables,
return check_func_dependency(join, list_tables & ~join->eliminated_tables,
&it, NULL, on_expr);
}
return FALSE; /* not eliminated */
@@ -1135,18 +1079,27 @@ eliminate_tables_for_list(Table_elimination *te, List<TABLE_LIST> *join_list,
*/
static
bool check_func_dependency(Table_elimination *te,
bool check_func_dependency(JOIN *join,
table_map dep_tables,
List_iterator<TABLE_LIST> *it,
TABLE_LIST *oj_tbl,
Item* cond)
{
uint and_level=0;
Equality_module* eq_dep= te->equality_deps;
Module_dep *bound_modules;
bzero(te->table_deps, sizeof(te->table_deps));
//psergey-todo: move allocs to somewhere else.
Table_elimination pte(join);
Table_elimination *te= &pte;
uint m= max(join->thd->lex->current_select->max_equal_elems,1);
uint max_elems= ((join->thd->lex->current_select->cond_count+1)*2 +
join->thd->lex->current_select->between_count)*m + 1 + 10;
if (!(te->equality_deps= new Equality_module[max_elems]))
return FALSE;
Equality_module* eq_dep= te->equality_deps;
/* Create Table_value objects for all tables we're trying to eliminate */
if (oj_tbl)
{
if (!get_table_value(te, oj_tbl->table))
@@ -1165,19 +1118,25 @@ bool check_func_dependency(Table_elimination *te,
}
}
/* Extract equalities from the ON expression */
/*
Analyze the the ON expression and create Equality_module objects and
Field_value objects for their left parts.
*/
if (build_eq_deps_for_cond(te, &eq_dep, &and_level, cond, dep_tables) ||
eq_dep == te->equality_deps)
return FALSE;
te->n_equality_deps= eq_dep - te->equality_deps;
/* Create objects for running wave algorithm */
if (!(te->outer_join_dep= new Outer_join_module(my_count_bits(dep_tables))) ||
setup_equality_deps(te, &bound_modules))
setup_equality_modules_deps(te, &bound_modules))
{
return FALSE; /* OOM, default to non-dependent */
}
DBUG_EXECUTE("test", dbug_print_deps(te); );
/* The running wave algorithm itself: */
Value_dep *bound_values= NULL;
while (bound_modules)
{