revision-id: 971ad0c2d10ecb81f463acab0c03111f32634696 (mariadb-10.4.1-78-g971ad0c2d10)
parent(s): d97a26a67dca82d166e9edefe5f950ea8a110dfd
author: Oleksandr Byelkin
committer: Oleksandr Byelkin
timestamp: 2019-01-15 10:05:05 +0100
message:
MDEV-16327 pre-requisits: isolation of LIMIT/OFFSET handling
---
sql/group_by_handler.cc | 8 +++----
sql/group_by_handler.h | 1 +
sql/item_subselect.cc | 2 +-
sql/opt_subselect.cc | 9 +++-----
sql/sql_class.cc | 44 +++++++++++-------------------------
sql/sql_class.h | 6 ++---
sql/sql_derived.cc | 2 +-
sql/sql_error.cc | 10 ++++-----
sql/sql_insert.cc | 7 ++----
sql/sql_lex.cc | 10 ++-------
sql/sql_lex.h | 59 ++++++++++++++++++++++++++++++++++++++++++++++++-
sql/sql_parse.cc | 13 ++++++-----
sql/sql_profile.cc | 10 ++++-----
sql/sql_repl.cc | 10 ++++-----
sql/sql_select.cc | 46 ++++++++++++++++++++------------------
sql/sql_union.cc | 36 +++++++++++++-----------------
16 files changed, 148 insertions(+), 125 deletions(-)
diff --git a/sql/group_by_handler.cc b/sql/group_by_handler.cc
index f18758a2d94..f5ed24370b1 100644
--- a/sql/group_by_handler.cc
+++ b/sql/group_by_handler.cc
@@ -40,7 +40,7 @@ int Pushdown_query::execute(JOIN *join)
{
int err;
ha_rows max_limit;
- ha_rows *reset_limit= 0;
+ bool reset_limit= FALSE;
Item **reset_item= 0;
THD *thd= handler->thd;
TABLE *table= handler->table;
@@ -52,11 +52,11 @@ int Pushdown_query::execute(JOIN *join)
if (store_data_in_temp_table)
{
max_limit= join->tmp_table_param.end_write_records;
- reset_limit= &join->unit->select_limit_cnt;
+ reset_limit= TRUE;
}
else
{
- max_limit= join->unit->select_limit_cnt;
+ max_limit= join->unit->lim.get_select_limit();
if (join->unit->fake_select_lex)
reset_item= &join->unit->fake_select_lex->select_limit;
}
@@ -112,7 +112,7 @@ int Pushdown_query::execute(JOIN *join)
break; // LIMIT reached
join->do_send_rows= 0; // Calculate FOUND_ROWS()
if (reset_limit)
- *reset_limit= HA_POS_ERROR;
+ join->unit->lim.set_unlimited();
if (reset_item)
*reset_item= 0;
}
diff --git a/sql/group_by_handler.h b/sql/group_by_handler.h
index d3f48a15c24..be981f0da5f 100644
--- a/sql/group_by_handler.h
+++ b/sql/group_by_handler.h
@@ -56,6 +56,7 @@ struct Query
ORDER *order_by;
Item *having;
// LIMIT
+ //ha_rows select_limit_cnt, offset_limit_cnt;
};
class group_by_handler
diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index 0ace59fd2fc..e860c3fa98d 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -2721,7 +2721,7 @@ bool Item_in_subselect::inject_in_to_exists_cond(JOIN *join_arg)
join_arg->thd->change_item_tree(&unit->global_parameters()->select_limit,
new (thd->mem_root)
Item_int(thd, (int32) 1));
- unit->select_limit_cnt= 1;
+ unit->lim.set_single_row();
DBUG_RETURN(false);
}
diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc
index c4c30c9b50d..e9284926385 100644
--- a/sql/opt_subselect.cc
+++ b/sql/opt_subselect.cc
@@ -5492,11 +5492,8 @@ int select_value_catcher::send_data(List<Item> &items)
DBUG_ASSERT(!assigned);
DBUG_ASSERT(items.elements == n_elements);
- if (unit->offset_limit_cnt)
- { // Using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // Using limit offset,count
Item *val_item;
List_iterator_fast<Item> li(items);
@@ -6289,7 +6286,7 @@ bool JOIN::choose_subquery_plan(table_map join_tables)
Set the limit of this JOIN object as well, because normally its being
set in the beginning of JOIN::optimize, which was already done.
*/
- select_limit= in_subs->unit->select_limit_cnt;
+ select_limit= in_subs->unit->lim.get_select_limit();
}
else if (in_subs->test_strategy(SUBS_IN_TO_EXISTS))
{
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 2952adbd3e6..ce6d71082fb 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -2936,11 +2936,8 @@ int select_send::send_data(List<Item> &items)
DBUG_ENTER("select_send::send_data");
/* unit is not set when using 'delete ... returning' */
- if (unit && unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(FALSE);
- }
+ if (unit && unit->lim.check_and_move_offset())
+ DBUG_RETURN(FALSE); // using limit offset,count
if (thd->killed == ABORT_QUERY)
DBUG_RETURN(FALSE);
@@ -3205,11 +3202,8 @@ int select_export::send_data(List<Item> &items)
String tmp(buff,sizeof(buff),&my_charset_bin),*res;
tmp.length(0);
- if (unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // using limit offset,count
if (thd->killed == ABORT_QUERY)
DBUG_RETURN(0);
row_count++;
@@ -3465,11 +3459,8 @@ int select_dump::send_data(List<Item> &items)
Item *item;
DBUG_ENTER("select_dump::send_data");
- if (unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // using limit offset,count
if (thd->killed == ABORT_QUERY)
DBUG_RETURN(0);
@@ -3508,11 +3499,8 @@ int select_singlerow_subselect::send_data(List<Item> &items)
MYF(current_thd->lex->ignore ? ME_WARNING : 0));
DBUG_RETURN(1);
}
- if (unit->offset_limit_cnt)
- { // Using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // Using limit offset,count
if (thd->killed == ABORT_QUERY)
DBUG_RETURN(0);
List_iterator_fast<Item> li(items);
@@ -3649,11 +3637,8 @@ int select_exists_subselect::send_data(List<Item> &items)
{
DBUG_ENTER("select_exists_subselect::send_data");
Item_exists_subselect *it= (Item_exists_subselect *)item;
- if (unit->offset_limit_cnt)
- { // Using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // Using limit offset,count
if (thd->killed == ABORT_QUERY)
DBUG_RETURN(0);
it->value= 1;
@@ -4060,12 +4045,9 @@ int select_dumpvar::send_data(List<Item> &items)
{
DBUG_ENTER("select_dumpvar::send_data");
- if (unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
- if (row_count++)
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // using limit offset,count
+ if (row_count++)
{
my_message(ER_TOO_MANY_ROWS, ER_THD(thd, ER_TOO_MANY_ROWS), MYF(0));
DBUG_RETURN(1);
diff --git a/sql/sql_class.h b/sql/sql_class.h
index b1da6e19247..7427b2745bc 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -5117,9 +5117,9 @@ class select_result :public select_result_sink
/* this method is called just before the first row of the table can be read */
virtual void prepare_to_read_rows() {}
- void reset_offset_limit()
+ void remove_offset_limit()
{
- unit->offset_limit_cnt= 0;
+ unit->lim.remove_offset();
}
/*
@@ -5786,7 +5786,7 @@ class select_union_direct :public select_unit
*/
DBUG_ASSERT(false); /* purecov: inspected */
}
- void reset_offset_limit_cnt()
+ void remove_offset_limit()
{
// EXPLAIN should never output to a select_union_direct
DBUG_ASSERT(false); /* purecov: inspected */
diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index 878aa715b84..4fd44a18550 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -1148,7 +1148,7 @@ bool mysql_derived_fill(THD *thd, LEX *lex, TABLE_LIST *derived)
{
SELECT_LEX *first_select= unit->first_select();
unit->set_limit(unit->global_parameters());
- if (unit->select_limit_cnt == HA_POS_ERROR)
+ if (unit->lim.is_unlimited())
first_select->options&= ~OPTION_FOUND_ROWS;
lex->current_select= first_select;
diff --git a/sql/sql_error.cc b/sql/sql_error.cc
index 8d639f9271d..6bb36dbb089 100644
--- a/sql/sql_error.cc
+++ b/sql/sql_error.cc
@@ -783,7 +783,7 @@ bool mysqld_show_warnings(THD *thd, ulong levels_to_show)
const Sql_condition *err;
SELECT_LEX *sel= thd->lex->first_select_lex();
SELECT_LEX_UNIT *unit= &thd->lex->unit;
- ulonglong idx= 0;
+ ha_rows idx;
Protocol *protocol=thd->protocol;
DBUG_ENTER("mysqld_show_warnings");
@@ -808,14 +808,14 @@ bool mysqld_show_warnings(THD *thd, ulong levels_to_show)
Diagnostics_area::Sql_condition_iterator it=
thd->get_stmt_da()->sql_conditions();
- while ((err= it++))
+ for (idx= 1; (err= it++) ; idx++)
{
/* Skip levels that the user is not interested in */
if (!(levels_to_show & ((ulong) 1 << err->get_level())))
continue;
- if (++idx <= unit->offset_limit_cnt)
- continue;
- if (idx > unit->select_limit_cnt)
+ if (unit->lim.check_and_move_offset())
+ continue; // using limit offset,count
+ if (idx > unit->lim.get_select_limit())
break;
protocol->prepare_for_resend();
protocol->store(warning_level_names[err->get_level()].str,
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index f5e4185db92..c4f60f0551c 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -3840,11 +3840,8 @@ int select_insert::send_data(List<Item> &values)
DBUG_ENTER("select_insert::send_data");
bool error=0;
- if (unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- DBUG_RETURN(0);
- }
+ if (unit->lim.check_and_move_offset())
+ DBUG_RETURN(0); // using limit offset,count
if (unlikely(thd->killed == ABORT_QUERY))
DBUG_RETURN(0);
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 1b8f448553b..2c298a17391 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -2321,8 +2321,7 @@ void st_select_lex_unit::init_query()
{
init_query_common();
set_linkage(GLOBAL_OPTIONS_TYPE);
- select_limit_cnt= HA_POS_ERROR;
- offset_limit_cnt= 0;
+ lim.set_unlimited();
union_distinct= 0;
prepared= optimized= optimized_2= executed= 0;
optimize_started= 0;
@@ -3462,12 +3461,7 @@ void st_select_lex_unit::set_limit(st_select_lex *sl)
{
DBUG_ASSERT(!thd->stmt_arena->is_stmt_prepare());
- offset_limit_cnt= sl->get_offset();
- select_limit_cnt= sl->get_limit();
- if (select_limit_cnt + offset_limit_cnt >= select_limit_cnt)
- select_limit_cnt+= offset_limit_cnt;
- else
- select_limit_cnt= HA_POS_ERROR;
+ lim.set_limit(sl->get_limit(), sl->get_offset());
}
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 40ba3b6e7b7..0270a4acfcc 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -816,6 +816,63 @@ void create_explain_query(LEX *lex, MEM_ROOT *mem_root);
void create_explain_query_if_not_exists(LEX *lex, MEM_ROOT *mem_root);
bool print_explain_for_slow_log(LEX *lex, THD *thd, String *str);
+class Select_limit_counters
+{
+ ha_rows offset_limit_cnt_start,
+ select_limit_cnt, offset_limit_cnt;
+
+ public:
+ Select_limit_counters():
+ offset_limit_cnt_start(0),
+ select_limit_cnt(0), offset_limit_cnt(0)
+ {};
+
+ void set_limit(ha_rows limit, ha_rows offset)
+ {
+ offset_limit_cnt_start= offset;
+ select_limit_cnt= limit;
+ if (select_limit_cnt + offset_limit_cnt_start >=
+ select_limit_cnt)
+ select_limit_cnt+= offset_limit_cnt_start;
+ else
+ select_limit_cnt= HA_POS_ERROR;
+ reset();
+ }
+
+ void set_single_row()
+ {
+ offset_limit_cnt= offset_limit_cnt_start= 0;
+ select_limit_cnt= 1;
+ }
+
+ void reset()
+ {
+ offset_limit_cnt= offset_limit_cnt_start;
+ }
+
+ bool is_unlimited()
+ { return select_limit_cnt == HA_POS_ERROR; }
+ void set_unlimited()
+ { select_limit_cnt= HA_POS_ERROR; offset_limit_cnt= 0; }
+
+ bool check_and_move_offset()
+ {
+ if (offset_limit_cnt)
+ {
+ offset_limit_cnt--;
+ return TRUE;
+ }
+ return FALSE;
+ }
+ void remove_offset() { offset_limit_cnt= 0; }
+
+ ha_rows get_select_limit()
+ { return select_limit_cnt; }
+ ha_rows get_offset_limit()
+ { return offset_limit_cnt; }
+};
+
+
class st_select_lex_unit: public st_select_lex_node {
protected:
TABLE_LIST result_table_list;
@@ -891,7 +948,7 @@ class st_select_lex_unit: public st_select_lex_node {
//node on which we should return current_select pointer after parsing subquery
st_select_lex *return_to;
/* LIMIT clause runtime counters */
- ha_rows select_limit_cnt, offset_limit_cnt;
+ Select_limit_counters lim;
/* not NULL if unit used in subselect, point to subselect item */
Item_subselect *item;
/*
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 7d6f71cda21..9e6600d65b6 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -4579,7 +4579,7 @@ mysql_execute_command(THD *thd)
select_lex->where,
select_lex->order_list.elements,
select_lex->order_list.first,
- unit->select_limit_cnt,
+ unit->lim.get_select_limit(),
lex->duplicates, lex->ignore,
&found, &updated);
MYSQL_UPDATE_DONE(res, found, updated);
@@ -4924,7 +4924,7 @@ mysql_execute_command(THD *thd)
res = mysql_delete(thd, all_tables,
select_lex->where, &select_lex->order_list,
- unit->select_limit_cnt, select_lex->options,
+ unit->lim.get_select_limit(), select_lex->options,
sel_result);
if (replaced_protocol)
@@ -5771,7 +5771,8 @@ mysql_execute_command(THD *thd)
res= mysql_ha_read(thd, first_table, lex->ha_read_mode, lex->ident.str,
lex->insert_list, lex->ha_rkey_mode, select_lex->where,
- unit->select_limit_cnt, unit->offset_limit_cnt);
+ unit->lim.get_select_limit(),
+ unit->lim.get_offset_limit());
break;
case SQLCOM_BEGIN:
@@ -6511,8 +6512,8 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables)
/*
Do like the original select_describe did: remove OFFSET from the
top-level LIMIT
- */
- result->reset_offset_limit();
+ */
+ result->remove_offset_limit();
if (lex->explain_json)
{
lex->explain->print_explain_json(result, lex->analyze_stmt);
@@ -7853,7 +7854,7 @@ void mysql_init_multi_delete(LEX *lex)
lex->sql_command= SQLCOM_DELETE_MULTI;
mysql_init_select(lex);
lex->first_select_lex()->select_limit= 0;
- lex->unit.select_limit_cnt= HA_POS_ERROR;
+ lex->unit.lim.set_unlimited();
lex->first_select_lex()->table_list.
save_and_clear(&lex->auxiliary_table_list);
lex->query_tables= 0;
diff --git a/sql/sql_profile.cc b/sql/sql_profile.cc
index 6ca21aebb37..e2b7b18faac 100644
--- a/sql/sql_profile.cc
+++ b/sql/sql_profile.cc
@@ -404,7 +404,7 @@ bool PROFILING::show_profiles()
MEM_ROOT *mem_root= thd->mem_root;
SELECT_LEX *sel= thd->lex->first_select_lex();
SELECT_LEX_UNIT *unit= &thd->lex->unit;
- ha_rows idx= 0;
+ ha_rows idx;
Protocol *protocol= thd->protocol;
void *iterator;
DBUG_ENTER("PROFILING::show_profiles");
@@ -428,9 +428,9 @@ bool PROFILING::show_profiles()
unit->set_limit(sel);
- for (iterator= history.new_iterator();
+ for (iterator= history.new_iterator(), idx= 1;
iterator != NULL;
- iterator= history.iterator_next(iterator))
+ iterator= history.iterator_next(iterator), idx++)
{
prof= history.iterator_value(iterator);
@@ -438,9 +438,9 @@ bool PROFILING::show_profiles()
double query_time_usecs= prof->m_end_time_usecs - prof->m_start_time_usecs;
- if (++idx <= unit->offset_limit_cnt)
+ if (unit->lim.check_and_move_offset())
continue;
- if (idx > unit->select_limit_cnt)
+ if (idx > unit->lim.get_select_limit())
break;
protocol->prepare_for_resend();
diff --git a/sql/sql_repl.cc b/sql/sql_repl.cc
index 2ee175293de..6f712750e41 100644
--- a/sql/sql_repl.cc
+++ b/sql/sql_repl.cc
@@ -3911,7 +3911,7 @@ bool mysql_show_binlog_events(THD* thd)
if (binary_log->is_open())
{
SELECT_LEX_UNIT *unit= &thd->lex->unit;
- ha_rows event_count, limit_start, limit_end;
+ ha_rows event_count;
my_off_t pos = MY_MAX(BIN_LOG_HEADER_SIZE, lex_mi->pos); // user-friendly
char search_file_name[FN_REFLEN], *name;
const char *log_file_name = lex_mi->log_file_name;
@@ -3926,8 +3926,6 @@ bool mysql_show_binlog_events(THD* thd)
}
unit->set_limit(thd->lex->current_select);
- limit_start= unit->offset_limit_cnt;
- limit_end= unit->select_limit_cnt;
name= search_file_name;
if (log_file_name)
@@ -4006,7 +4004,7 @@ bool mysql_show_binlog_events(THD* thd)
description_event,
opt_master_verify_checksum)); )
{
- if (event_count >= limit_start &&
+ if (!unit->lim.check_and_move_offset() &&
ev->net_send(protocol, linfo.log_file_name, pos))
{
errmsg = "Net error";
@@ -4040,11 +4038,11 @@ bool mysql_show_binlog_events(THD* thd)
pos = my_b_tell(&log);
- if (++event_count >= limit_end)
+ if (++event_count >= unit->lim.get_select_limit())
break;
}
- if (unlikely(event_count < limit_end && log.error))
+ if (unlikely(event_count < unit->lim.get_select_limit() && log.error))
{
errmsg = "Wrong offset or I/O error";
mysql_mutex_unlock(log_lock);
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 978f0785887..aa4c40866a9 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -1508,7 +1508,7 @@ JOIN::optimize_inner()
{
DBUG_ENTER("JOIN::optimize");
subq_exit_fl= false;
- do_send_rows = (unit->select_limit_cnt) ? 1 : 0;
+ do_send_rows = (unit->lim.get_select_limit()) ? 1 : 0;
DEBUG_SYNC(thd, "before_join_optimize");
@@ -1579,9 +1579,9 @@ JOIN::optimize_inner()
DBUG_RETURN(-1);
row_limit= ((select_distinct || order || group_list) ? HA_POS_ERROR :
- unit->select_limit_cnt);
+ unit->lim.get_select_limit());
/* select_limit is used to decide if we are likely to scan the whole table */
- select_limit= unit->select_limit_cnt;
+ select_limit= unit->lim.get_select_limit();
if (having || (select_options & OPTION_FOUND_ROWS))
select_limit= HA_POS_ERROR;
#ifdef HAVE_REF_TO_FIELDS // Not done yet
@@ -1790,9 +1790,10 @@ JOIN::optimize_inner()
thd->change_item_tree(&sel->having, having);
}
if (cond_value == Item::COND_FALSE || having_value == Item::COND_FALSE ||
- (!unit->select_limit_cnt && !(select_options & OPTION_FOUND_ROWS)))
+ (!unit->lim.get_select_limit() &&
+ !(select_options & OPTION_FOUND_ROWS)))
{ /* Impossible cond */
- if (unit->select_limit_cnt)
+ if (unit->lim.get_select_limit())
{
DBUG_PRINT("info", (having_value == Item::COND_FALSE ?
"Impossible HAVING" : "Impossible WHERE"));
@@ -3314,7 +3315,7 @@ bool JOIN::make_aggr_tables_info()
*/
sort_tab->filesort->limit=
(has_group_by || (join_tab + table_count > curr_tab + 1)) ?
- select_limit : unit->select_limit_cnt;
+ select_limit : unit->lim.get_select_limit();
}
if (!only_const_tables() &&
!join_tab[const_tables].filesort &&
@@ -3698,8 +3699,7 @@ JOIN::reinit()
{
DBUG_ENTER("JOIN::reinit");
- unit->offset_limit_cnt= (ha_rows)(select_lex->offset_limit ?
- select_lex->offset_limit->val_uint() : 0);
+ unit->lim.reset();
first_record= false;
group_sent= false;
@@ -5157,7 +5157,7 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
for (i= 0; i < join->table_count ; i++)
records*= join->best_positions[i].records_read ?
(ha_rows)join->best_positions[i].records_read : 1;
- set_if_smaller(records, unit->select_limit_cnt);
+ set_if_smaller(records, unit->lim.get_select_limit());
join->select_lex->increase_derived_records(records);
}
}
@@ -7446,7 +7446,7 @@ best_access_path(JOIN *join,
if (!best_key &&
idx == join->const_tables &&
s->table == join->sort_by_table &&
- join->unit->select_limit_cnt >= records)
+ join->unit->lim.get_select_limit() >= records)
join->sort_by_table= (TABLE*) 1; // Must use temporary table
DBUG_VOID_RETURN;
@@ -10799,7 +10799,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
!tab->loosescan_match_tab && // (1)
((cond && (!tab->keys.is_subset(tab->const_keys) && i > 0)) ||
(!tab->const_keys.is_clear_all() && i == join->const_tables &&
- join->unit->select_limit_cnt <
+ join->unit->lim.get_select_limit() <
join->best_positions[i].records_read &&
!(join->select_options & OPTION_FOUND_ROWS))))
{
@@ -10823,7 +10823,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
(join->select_options &
OPTION_FOUND_ROWS ?
HA_POS_ERROR :
- join->unit->select_limit_cnt), 0,
+ join->unit->lim.get_select_limit()), 0,
FALSE, FALSE) < 0)
{
/*
@@ -10837,7 +10837,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
(join->select_options &
OPTION_FOUND_ROWS ?
HA_POS_ERROR :
- join->unit->select_limit_cnt),0,
+ join->unit->lim.get_select_limit()),0,
FALSE, FALSE) < 0)
DBUG_RETURN(1); // Impossible WHERE
}
@@ -20581,7 +20581,7 @@ end_send(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
}
++join->send_records;
- if (join->send_records >= join->unit->select_limit_cnt &&
+ if (join->send_records >= join->unit->lim.get_select_limit() &&
!join->do_send_rows)
{
/*
@@ -20599,7 +20599,7 @@ end_send(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
DBUG_RETURN(NESTED_LOOP_QUERY_LIMIT);
}
}
- if (join->send_records >= join->unit->select_limit_cnt &&
+ if (join->send_records >= join->unit->lim.get_select_limit() &&
join->do_send_rows)
{
if (join->select_options & OPTION_FOUND_ROWS)
@@ -20740,13 +20740,13 @@ end_send_group(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
DBUG_RETURN(NESTED_LOOP_ERROR); /* purecov: inspected */
if (end_of_records)
DBUG_RETURN(NESTED_LOOP_OK);
- if (join->send_records >= join->unit->select_limit_cnt &&
+ if (join->send_records >= join->unit->lim.get_select_limit() &&
join->do_send_rows)
{
if (!(join->select_options & OPTION_FOUND_ROWS))
DBUG_RETURN(NESTED_LOOP_QUERY_LIMIT); // Abort nicely
join->do_send_rows=0;
- join->unit->select_limit_cnt = HA_POS_ERROR;
+ join->unit->lim.set_unlimited();
}
else if (join->send_records >= join->fetch_limit)
{
@@ -20831,7 +20831,7 @@ end_write(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
if (!(join->select_options & OPTION_FOUND_ROWS))
DBUG_RETURN(NESTED_LOOP_QUERY_LIMIT);
join->do_send_rows=0;
- join->unit->select_limit_cnt = HA_POS_ERROR;
+ join->unit->lim.set_unlimited();
}
}
}
@@ -22142,7 +22142,9 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
(tab->join->select_options &
OPTION_FOUND_ROWS) ?
HA_POS_ERROR :
- tab->join->unit->select_limit_cnt,TRUE,
+ tab->join->unit->
+ lim.get_select_limit(),
+ TRUE,
TRUE, FALSE) <= 0;
if (res)
{
@@ -22244,7 +22246,7 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
select->test_quick_select(join->thd, tmp_map, 0,
join->select_options & OPTION_FOUND_ROWS ?
HA_POS_ERROR :
- join->unit->select_limit_cnt,
+ join->unit->lim.get_select_limit(),
TRUE, FALSE, FALSE);
if (cond_saved)
@@ -22671,7 +22673,7 @@ JOIN_TAB::remove_duplicates()
if (!field_count && !(join->select_options & OPTION_FOUND_ROWS) && !having)
{ // only const items with no OPTION_FOUND_ROWS
- join->unit->select_limit_cnt= 1; // Only send first row
+ join->unit->lim.set_single_row(); // Only send first row
DBUG_RETURN(false);
}
@@ -24859,7 +24861,7 @@ int JOIN::rollup_send_data(uint idx)
copy_ref_ptr_array(ref_ptrs, rollup.ref_pointer_arrays[i]);
if ((!having || having->val_int()))
{
- if (send_records < unit->select_limit_cnt && do_send_rows &&
+ if (send_records < unit->lim.get_select_limit() && do_send_rows &&
(res= result->send_data(rollup.fields[i])) > 0)
return 1;
if (!res)
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index ca8a5e7a8b3..d563301a339 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -110,11 +110,8 @@ int select_unit::send_data(List<Item> &values)
{
int rc;
int not_reported_error= 0;
- if (unit->offset_limit_cnt)
- { // using limit offset,count
- unit->offset_limit_cnt--;
- return 0;
- }
+ if (unit->lim.check_and_move_offset())
+ return 0; // using limit offset,count
if (thd->killed == ABORT_QUERY)
return 0;
if (table->no_rows_with_nulls)
@@ -883,8 +880,7 @@ bool st_select_lex_unit::prepare(TABLE_LIST *derived_arg,
else
{
sl->join->result= result;
- select_limit_cnt= HA_POS_ERROR;
- offset_limit_cnt= 0;
+ lim.set_unlimited();
if (!sl->join->procedure &&
result->prepare(sl->join->fields_list, this))
{
@@ -1317,7 +1313,7 @@ bool st_select_lex_unit::optimize()
if (sl->tvc)
{
sl->tvc->select_options=
- (select_limit_cnt == HA_POS_ERROR || sl->braces) ?
+ (lim.is_unlimited() || sl->braces) ?
sl->options & ~OPTION_FOUND_ROWS : sl->options | found_rows_for_union;
if (sl->tvc->optimize(thd))
{
@@ -1337,13 +1333,13 @@ bool st_select_lex_unit::optimize()
set_limit(sl);
if (sl == global_parameters() || describe)
{
- offset_limit_cnt= 0;
+ lim.remove_offset();
/*
We can't use LIMIT at this stage if we are using ORDER BY for the
whole query
*/
if (sl->order_list.first || describe)
- select_limit_cnt= HA_POS_ERROR;
+ lim.set_unlimited();
}
/*
@@ -1352,7 +1348,7 @@ bool st_select_lex_unit::optimize()
Otherwise, SQL_CALC_FOUND_ROWS should be done on all sub parts.
*/
sl->join->select_options=
- (select_limit_cnt == HA_POS_ERROR || sl->braces) ?
+ (lim.is_unlimited() || sl->braces) ?
sl->options & ~OPTION_FOUND_ROWS : sl->options | found_rows_for_union;
saved_error= sl->join->optimize();
@@ -1432,13 +1428,13 @@ bool st_select_lex_unit::exec()
set_limit(sl);
if (sl == global_parameters() || describe)
{
- offset_limit_cnt= 0;
+ lim.remove_offset();
/*
We can't use LIMIT at this stage if we are using ORDER BY for the
whole query
*/
if (sl->order_list.first || describe)
- select_limit_cnt= HA_POS_ERROR;
+ lim.set_unlimited();
}
/*
@@ -1449,14 +1445,14 @@ bool st_select_lex_unit::exec()
if (sl->tvc)
{
sl->tvc->select_options=
- (select_limit_cnt == HA_POS_ERROR || sl->braces) ?
+ (lim.is_unlimited() || sl->braces) ?
sl->options & ~OPTION_FOUND_ROWS : sl->options | found_rows_for_union;
saved_error= sl->tvc->optimize(thd);
}
else
{
- sl->join->select_options=
- (select_limit_cnt == HA_POS_ERROR || sl->braces) ?
+ sl->join->select_options=
+ (lim.is_unlimited() || sl->braces) ?
sl->options & ~OPTION_FOUND_ROWS : sl->options | found_rows_for_union;
saved_error= sl->join->optimize();
}
@@ -1478,9 +1474,7 @@ bool st_select_lex_unit::exec()
}
if (!sl->tvc)
saved_error= sl->join->error;
- offset_limit_cnt= (ha_rows)(sl->offset_limit ?
- sl->offset_limit->val_uint() :
- 0);
+ lim.reset();
if (likely(!saved_error))
{
examined_rows+= thd->get_examined_row_count();
@@ -1507,8 +1501,8 @@ bool st_select_lex_unit::exec()
DBUG_RETURN(1);
}
}
- if (found_rows_for_union && !sl->braces &&
- select_limit_cnt != HA_POS_ERROR)
+ if (found_rows_for_union && !sl->braces &&
+ !lim.is_unlimited())
{
/*
This is a union without braces. Remember the number of rows that
