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[SHOW] EXPLAIN UPDATE/DELETE, code re-structuring

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- Make EXPLAIN UPDATE/DELETE use "Query Plan Footprints", too.
This commit is contained in:
Sergey Petrunya
2013-06-18 21:08:34 +04:00
parent 1c6fc3f6b9
commit 1951d40a88
6 changed files with 152 additions and 115 deletions
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68
sql/sql_update.cc
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@ -276,9 +276,7 @@ int mysql_update(THD *thd,
ulonglong id;
List<Item> all_fields;
killed_state killed_status= NOT_KILLED;
Update_plan query_plan;
query_plan.index= MAX_KEY;
query_plan.using_filesort= FALSE;
Update_plan *query_plan;
bool apc_target_enabled= false; // means was enabled *by code this function*
DBUG_ENTER("mysql_update");
@ -317,9 +315,12 @@ int mysql_update(THD *thd,
/* Calculate "table->covering_keys" based on the WHERE */
table->covering_keys= table->s->keys_in_use;
table->quick_keys.clear_all();
query_plan.select_lex= &thd->lex->select_lex;
query_plan.table= table;
query_plan= new Update_plan;
query_plan->index= MAX_KEY;
query_plan->using_filesort= FALSE;
query_plan->select_lex= &thd->lex->select_lex;
query_plan->table= table;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
/* Force privilege re-checking for views after they have been opened. */
want_privilege= (table_list->view ? UPDATE_ACL :
@ -378,7 +379,7 @@ int mysql_update(THD *thd,
if (cond_value == Item::COND_FALSE)
{
limit= 0; // Impossible WHERE
query_plan.set_impossible_where();
query_plan->set_impossible_where();
if (thd->lex->describe)
goto exit_without_my_ok;
}
@ -411,7 +412,7 @@ int mysql_update(THD *thd,
if (error || !limit || thd->is_error() ||
(select && select->check_quick(thd, safe_update, limit)))
{
query_plan.set_impossible_where();
query_plan->set_impossible_where();
if (thd->lex->describe)
goto exit_without_my_ok;
@ -453,16 +454,16 @@ int mysql_update(THD *thd,
if (select && select->quick && select->quick->unique_key_range())
{ // Single row select (always "ordered"): Ok to use with key field UPDATE
need_sort= FALSE;
query_plan.index= MAX_KEY;
query_plan->index= MAX_KEY;
used_key_is_modified= FALSE;
}
else
{
query_plan.index= get_index_for_order(order, table, select, limit,
&need_sort, &reverse);
query_plan->index= get_index_for_order(order, table, select, limit,
&need_sort, &reverse);
if (select && select->quick)
{
DBUG_ASSERT(need_sort || query_plan.index == select->quick->index);
DBUG_ASSERT(need_sort || query_plan->index == select->quick->index);
used_key_is_modified= (!select->quick->unique_key_range() &&
select->quick->is_keys_used(table->write_set));
}
@ -470,11 +471,11 @@ int mysql_update(THD *thd,
{
if (need_sort)
{ // Assign table scan index to check below for modified key fields:
query_plan.index= table->file->key_used_on_scan;
query_plan->index= table->file->key_used_on_scan;
}
if (query_plan.index != MAX_KEY)
if (query_plan->index != MAX_KEY)
{ // Check if we are modifying a key that we are used to search with:
used_key_is_modified= is_key_used(table, query_plan.index, table->write_set);
used_key_is_modified= is_key_used(table, query_plan->index, table->write_set);
}
}
}
@ -484,10 +485,11 @@ int mysql_update(THD *thd,
- Save the decisions in the query plan
- if we're running EXPLAIN UPDATE, get out
*/
query_plan.select= select;
query_plan.possible_keys= table->quick_keys;
query_plan.table_rows= table->file->stats.records;
thd->lex->upd_del_plan= &query_plan;
query_plan->select= select;
query_plan->possible_keys= table->quick_keys;
query_plan->table_rows= table->file->stats.records;
thd->lex->query_plan_footprint= new QPF_query;
thd->lex->query_plan_footprint->upd_del_plan= query_plan;
/*
Ok, we have generated a query plan for the UPDATE.
@ -496,7 +498,8 @@ int mysql_update(THD *thd,
*/
if (thd->lex->describe)
goto exit_without_my_ok;
query_plan->save_query_plan_footprint();
thd->apc_target.enable();
apc_target_enabled= true;
DBUG_EXECUTE_IF("show_explain_probe_update_exec_start",
@ -515,8 +518,8 @@ int mysql_update(THD *thd,
DBUG_ASSERT(table->read_set == &table->def_read_set);
DBUG_ASSERT(table->write_set == &table->def_write_set);
if (query_plan.index < MAX_KEY && old_covering_keys.is_set(query_plan.index))
table->add_read_columns_used_by_index(query_plan.index);
if (query_plan->index < MAX_KEY && old_covering_keys.is_set(query_plan->index))
table->add_read_columns_used_by_index(query_plan->index);
else
table->use_all_columns();
@ -582,13 +585,13 @@ int mysql_update(THD *thd,
Full index scan must be started with init_read_record_idx
*/
if (query_plan.index == MAX_KEY || (select && select->quick))
if (query_plan->index == MAX_KEY || (select && select->quick))
{
if (init_read_record(&info, thd, table, select, 0, 1, FALSE))
goto err;
}
else
init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse);
init_read_record_idx(&info, thd, table, 1, query_plan->index, reverse);
thd_proc_info(thd, "Searching rows for update");
ha_rows tmp_limit= limit;
@ -1002,6 +1005,12 @@ err:
if (apc_target_enabled)
thd->apc_target.disable();
if (thd->lex->query_plan_footprint)
{
delete thd->lex->query_plan_footprint;
thd->lex->query_plan_footprint= NULL;
}
delete select;
free_underlaid_joins(thd, select_lex);
table->disable_keyread();
@ -1010,22 +1019,25 @@ err:
exit_without_my_ok:
DBUG_ASSERT(!apc_target_enabled);
thd->lex->upd_del_plan= &query_plan;
query_plan->save_query_plan_footprint();
thd->lex->query_plan_footprint->upd_del_plan= query_plan;
select_send *result;
bool printed_anything;
if (!(result= new select_send()))
return 1; /* purecov: inspected */
List<Item> dummy; /* note: looked in 5.6 and they too use a dummy list like this */
result->prepare(dummy, &thd->lex->unit);
thd->send_explain_fields(result);
int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything);
int err2= thd->lex->query_plan_footprint->print_explain(result, 0);
if (err2)
result->abort_result_set();
else
result->send_eof();
delete thd->lex->query_plan_footprint;
thd->lex->query_plan_footprint= NULL;
delete select;
free_underlaid_joins(thd, select_lex);
DBUG_RETURN((error >= 0 || thd->is_error()) ? 1 : 0);