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Commit 69c386d9 authored by Sergey Petrunya's avatar Sergey Petrunya
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Code cleanup

parent eeb67132
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Showing with 60 additions and 58 deletions
mysql-test/r/explain_non_select.result
View file @ 69c386d9
......@@ -102,3 +102,15 @@ id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 8 Using where
1 SIMPLE t1 ref a a 5 test.t0.a 4 Using index
drop table t0, t1;
#
# Try DELETE ... RETURNING ...
#
create table t0 (a int);
insert into t0 values (1),(2),(3),(4);
explain delete from t0 where a=1 returning a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 4 Using where
explain delete from t0 returning a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 4
drop table t0;
sql/opt_qpf.cc
View file @ 69c386d9
......@@ -14,8 +14,6 @@ QPF_query::QPF_query()
{
upd_del_plan= NULL;
operations= 0;
//memset(&unions, 0, sizeof(unions));
//memset(&selects, 0, sizeof(selects));
}
......@@ -105,18 +103,13 @@ int QPF_query::print_explain(select_result_sink *output,
}
else
{
// Start with id=1
// Start printing from id=1
QPF_node *node= get_node(1);
return node->print_explain(this, output, explain_flags);
}
}
void QPF_union::push_table_name(List<Item> *item_list)
{
}
static void push_str(List<Item> *item_list, const char *str)
{
item_list->push_back(new Item_string(str,
......@@ -134,7 +127,7 @@ static void push_string(List<Item> *item_list, String *str)
int QPF_union::print_explain(QPF_query *query, select_result_sink *output,
uint8 explain_flags)
{
// print all children, in order
/* print all UNION children, in order */
for (int i= 0; i < (int) union_members.elements(); i++)
{
QPF_select *sel= query->get_select(union_members.at(i));
......@@ -152,7 +145,6 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output,
push_str(&item_list, fake_select_type);
/* `table` column: something like "<union1,2>" */
//
{
char table_name_buffer[SAFE_NAME_LEN];
uint childno= 0;
......@@ -180,8 +172,6 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output,
const CHARSET_INFO *cs= system_charset_info;
item_list.push_back(new Item_string(table_name_buffer, len, cs));
}
//
push_table_name(&item_list);
/* `partitions` column */
if (explain_flags & DESCRIBE_PARTITIONS)
......@@ -222,10 +212,18 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output,
if (output->send_data(item_list))
return 1;
/*
Print all subquery children (UNION children have already been printed at
the start of this function)
*/
return print_explain_for_children(query, output, explain_flags);
}
/*
Print EXPLAINs for all children nodes (i.e. for subqueries)
*/
int QPF_node::print_explain_for_children(QPF_query *query,
select_result_sink *output,
uint8 explain_flags)
......@@ -301,6 +299,12 @@ int QPF_select::print_explain(QPF_query *query, select_result_sink *output,
}
void QPF_table_access::push_extra(enum Extra_tag extra_tag)
{
extra_tags.append(extra_tag);
}
int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_flags,
uint select_id, const char *select_type,
bool using_temporary, bool using_filesort)
......@@ -422,13 +426,17 @@ int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_fl
}
/*
Elements in this array match members of enum Extra_tag, defined in opt_qpf.h.
*/
const char * extra_tag_text[]=
{
"ET_none",
"Using index condition",
"Using index condition(BKA)",
"Using ", //special
"Range checked for each record (index map: 0x", //special
"Using ", // special handling
"Range checked for each record (index map: 0x", // special handling
"Using where with pushed condition",
"Using where",
"Not exists",
......@@ -443,17 +451,17 @@ const char * extra_tag_text[]=
"Scanned 1 database",
"Scanned all databases",
"Using index for group-by", // Special?
"Using index for group-by", // special handling
"USING MRR: DONT PRINT ME", // Special!
"USING MRR: DONT PRINT ME", // special handling
"Distinct",
"LooseScan",
"Start temporary",
"End temporary",
"FirstMatch", //TODO: also handle special variant!
"FirstMatch", // special handling
"Using join buffer", // Special!,
"Using join buffer", // special handling
"const row not found",
"unique row not found",
......
sql/opt_qpf.h
View file @ 69c386d9
......@@ -146,7 +146,6 @@ public:
{
union_members.append(select_no);
}
void push_table_name(List<Item> *item_list);
int print_explain(QPF_query *query, select_result_sink *output,
uint8 explain_flags);
......@@ -231,6 +230,11 @@ private:
};
/*
Some of the tags have matching text. See extra_tag_text for text names, and
QPF_table_access::append_tag_name() for code to convert from tag form to text
form.
*/
enum Extra_tag
{
ET_none= 0, /* not-a-tag */
......@@ -347,7 +351,6 @@ public:
StringBuffer<64> mrr_type;
// valid with ET_USING_JOIN_BUFFER
//StringBuffer<64> join_buffer_type;
QPF_BKA_TYPE bka_type;
//TABLE *firstmatch_table;
......
sql/sql_select.cc
View file @ 69c386d9
......@@ -11172,7 +11172,7 @@ void JOIN::cleanup(bool full)
if (full)
{
/* Save it again */
#if 0
#if 0 psergey-todo: remove?
if (select_lex->select_number != UINT_MAX &&
select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ &&
have_query_plan != QEP_NOT_PRESENT_YET &&
......@@ -22487,11 +22487,7 @@ void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res)
}
/////////////////////////////////////////////////////////////////////////////////////////////////
void QPF_table_access::push_extra(enum Extra_tag extra_tag)
{
extra_tags.append(extra_tag);
}
///////////////////////////////////////////////////////////////////////////////
void append_possible_keys(String *str, TABLE *table, key_map possible_keys)
{
......@@ -22548,24 +22544,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order,
}
else if (join->select_lex == join->unit->fake_select_lex)
{
#if 0
select_lex->set_explain_type(on_the_fly);
QPF_union *qp_union= new (output->mem_root) QPF_union;
qp_node= qp_union;
SELECT_LEX *child;
for (child= select_lex->master_unit()->first_select(); child;
child=child->next_select())
{
qp_union->add_select(child->select_number);
}
qp_union->fake_select_type= select_lex->type;
qp_union->using_filesort=
test(select_lex->master_unit()->global_parameters->order_list.first);
output->add_node(qp_union);
#endif
/* Do nothing, QPF_union will create and print fake_select_lex */
}
else if (!join->select_lex->master_unit()->derived ||
join->select_lex->master_unit()->derived->is_materialized_derived())
......@@ -22713,7 +22692,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order,
// tmp2 holds key_name
// tmp3 holds key_length
// tmp4 holds ref?
// tmp4 holds ref
if (tab_type == JT_NEXT)
{
key_info= table->key_info+tab->index;
......@@ -23074,16 +23053,16 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order,
/*
This function servers as "shortcut point" for EXPLAIN queries.
This function serves as "shortcut point" for EXPLAIN queries.
For UNIONs and JOINs, EXPLAIN statement executes just like its SELECT
statement would execute, except that JOIN::exec() will call select_describe()
instead of actually executing the query.
The EXPLAIN statement executes just like its SELECT counterpart would
execute, except that JOIN::exec() will call select_describe() instead of
actually executing the query.
The purpose of select_describe() is:
- update the query plan with info about last-minute choices made at the start
of JOIN::exec
- Invoke "pseudo-execution" for the children subqueries.
Inside select_describe():
- Query plan is updated with latest QEP choices made at the start of
JOIN::exec().
- the proces of "almost execution" is invoked for the children subqueries.
Overall, select_describe() is a legacy of old EXPLAIN implementation and
should be removed.
......@@ -23096,9 +23075,10 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
select_result *result=join->result;
DBUG_ENTER("select_describe");
// Update the QPF:
/* Update the QPF with latest values of using_temporary, using_filesort */
QPF_select *qp;
if ((qp= thd->lex->query_plan_footprint->get_select(join->select_lex->select_number)))
uint select_nr= join->select_lex->select_number;
if ((qp= thd->lex->query_plan_footprint->get_select(select_nr)))
{
qp->using_temporary= need_tmp_table;
qp->using_filesort= need_order;
......
sql/sql_select.h
View file @ 69c386d9
......@@ -259,7 +259,6 @@ typedef struct st_join_table {
/* Special content for EXPLAIN 'Extra' column or NULL if none */
enum Extra_tag info;
//const char *info;
/*
Bitmap of TAB_INFO_* bits that encodes special line for EXPLAIN 'Extra'
......
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