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Merge 10.2 into 10.3

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This commit is contained in:
Marko Mäkelä
2021-03-18 12:34:48 +02:00
parent eb7c5530ec c557e9540a
commit 19052b6deb
244 changed files with 5158 additions and 6822 deletions
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88
sql/sql_join_cache.cc
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@ -1650,7 +1650,7 @@ void JOIN_CACHE::get_record_by_pos(uchar *rec_ptr)
}
/*
/*
Get the match flag from the referenced record: the default implementation
SYNOPSIS
@ -1662,6 +1662,7 @@ void JOIN_CACHE::get_record_by_pos(uchar *rec_ptr)
get the match flag for the record pointed by the reference at the position
rec_ptr. If the match flag is placed in one of the previous buffers the
function first reaches the linked record fields in this buffer.
The function returns the value of the first encountered match flag.
RETURN VALUE
match flag for the record at the position rec_ptr
@ -1686,6 +1687,39 @@ enum JOIN_CACHE::Match_flag JOIN_CACHE::get_match_flag_by_pos(uchar *rec_ptr)
/*
Get the match flag for the referenced record from specified join buffer
SYNOPSIS
get_match_flag_by_pos_from_join_buffer()
rec_ptr position of the first field of the record in the join buffer
tab join table with join buffer where to look for the match flag
DESCRIPTION
This default implementation of the get_match_flag_by_pos_from_join_buffer
method gets the match flag for the record pointed by the reference at the
position rec_ptr from the join buffer attached to the join table tab.
RETURN VALUE
match flag for the record at the position rec_ptr from the join
buffer attached to the table tab.
*/
enum JOIN_CACHE::Match_flag
JOIN_CACHE::get_match_flag_by_pos_from_join_buffer(uchar *rec_ptr,
JOIN_TAB *tab)
{
DBUG_ASSERT(tab->cache && tab->cache->with_match_flag);
for (JOIN_CACHE *cache= this; ; )
{
if (cache->join_tab == tab)
return (enum Match_flag) rec_ptr[0];
cache= cache->prev_cache;
rec_ptr= cache->get_rec_ref(rec_ptr);
}
}
/*
Calculate the increment of the auxiliary buffer for a record write
SYNOPSIS
@ -1955,6 +1989,10 @@ bool JOIN_CACHE::read_referenced_field(CACHE_FIELD *copy,
If the record is skipped the value of 'pos' is set to point to the position
right after the record.
NOTE
Currently this function is called only when generating null complemented
records for outer joins (=> only when join_tab->first_unmatched != NULL).
RETURN VALUE
TRUE the match flag is set to MATCH_FOUND and the record has been skipped
FALSE otherwise
@ -1967,7 +2005,9 @@ bool JOIN_CACHE::skip_if_matched()
if (prev_cache)
offset+= prev_cache->get_size_of_rec_offset();
/* Check whether the match flag is MATCH_FOUND */
if (get_match_flag_by_pos(pos+offset) == MATCH_FOUND)
if (get_match_flag_by_pos_from_join_buffer(pos+offset,
join_tab->first_unmatched) ==
MATCH_FOUND)
{
pos+= size_of_rec_len + get_rec_length(pos);
return TRUE;
@ -1984,13 +2024,23 @@ bool JOIN_CACHE::skip_if_matched()
DESCRIPTION
This default implementation of the virtual function skip_if_not_needed_match
skips the next record from the join buffer if its match flag is not
MATCH_NOT_FOUND, and, either its value is MATCH_FOUND and join_tab is the
first inner table of an inner join, or, its value is MATCH_IMPOSSIBLE
and join_tab is the first inner table of an outer join.
skips the next record from the join when generating join extensions
for the records in the join buffer depending on the value of the match flag.
- In the case of a semi-nest the match flag may be in two states
{MATCH_NOT_FOUND, MATCH_FOUND}. The record is skipped if the flag is set
to MATCH_FOUND.
- In the case of a outer join nest when not_exists optimization is applied
the match may be in three states {MATCH_NOT_FOUND, MATCH_IMPOSSIBLE,
MATCH_FOUND. The record is skipped if the flag is set to MATCH_FOUND or
to MATCH_IMPOSSIBLE.
If the record is skipped the value of 'pos' is set to point to the position
right after the record.
NOTE
Currently the function is called only when generating non-null complemented
extensions for records in the join buffer.
RETURN VALUE
TRUE the record has to be skipped
FALSE otherwise
@ -2001,11 +2051,19 @@ bool JOIN_CACHE::skip_if_not_needed_match()
DBUG_ASSERT(with_length);
enum Match_flag match_fl;
uint offset= size_of_rec_len;
bool skip= FALSE;
if (prev_cache)
offset+= prev_cache->get_size_of_rec_offset();
if ((match_fl= get_match_flag_by_pos(pos+offset)) != MATCH_NOT_FOUND &&
(join_tab->check_only_first_match() == (match_fl == MATCH_FOUND)) )
if (!join_tab->check_only_first_match())
return FALSE;
match_fl= get_match_flag_by_pos(pos+offset);
skip= join_tab->first_sj_inner_tab ?
match_fl == MATCH_FOUND : // the case of semi-join
match_fl != MATCH_NOT_FOUND; // the case of outer-join
if (skip)
{
pos+= size_of_rec_len + get_rec_length(pos);
return TRUE;
@ -2105,7 +2163,14 @@ enum_nested_loop_state JOIN_CACHE::join_records(bool skip_last)
goto finish;
}
join_tab->not_null_compl= FALSE;
/* Prepare for generation of null complementing extensions */
/*
Prepare for generation of null complementing extensions.
For all inner tables of the outer join operation for which
regular matches have been just found the field 'first_unmatched'
is set to point the the first inner table. After all null
complement rows are generated for this outer join this field
is set back to NULL.
*/
for (tab= join_tab->first_inner; tab <= join_tab->last_inner; tab++)
tab->first_unmatched= join_tab->first_inner;
}
@ -2222,7 +2287,10 @@ enum_nested_loop_state JOIN_CACHE::join_matching_records(bool skip_last)
int error;
enum_nested_loop_state rc= NESTED_LOOP_OK;
join_tab->table->null_row= 0;
bool check_only_first_match= join_tab->check_only_first_match();
bool check_only_first_match=
join_tab->check_only_first_match() &&
(!join_tab->first_inner || // semi-join case
join_tab->first_inner == join_tab->first_unmatched); // outer join case
bool outer_join_first_inner= join_tab->is_first_inner_for_outer_join();
DBUG_ENTER("JOIN_CACHE::join_matching_records");