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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)
......@@ -221,11 +211,19 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output,
//output->unit.offset_limit_cnt= 0;
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.
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.
This function serves as "shortcut point" for EXPLAIN queries.
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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