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MDEV-22665: Print ranges in the optimizer trace created for non-indexed columns when optimizer_use_condition_selectivity >2

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Now the optimizer trace shows the ranges constructed while getting estimates from EITS
This commit is contained in:
Varun Gupta
2020-05-22 21:15:17 +05:30
parent 205b0ce6ad
commit 4c3cbe2392
5 changed files with 240 additions and 38 deletions
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96
mysql-test/main/opt_trace.result
View File

@@ -108,6 +108,7 @@ select * from v1 {
"selectivity_for_columns": [
{
"column_name": "a",
"ranges": ["1 <= a <= 1"],
"selectivity_from_histogram": 0.5
}
],
@@ -253,6 +254,7 @@ select * from (select * from t1 where t1.a=1)q {
"selectivity_for_columns": [
{
"column_name": "a",
"ranges": ["1 <= a <= 1"],
"selectivity_from_histogram": 0.5
}
],
@@ -403,6 +405,7 @@ select * from v2 {
"selectivity_for_columns": [
{
"column_name": "a",
"ranges": ["1 <= a <= 1"],
"selectivity_from_histogram": 0.5
}
],
@@ -1416,10 +1419,12 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
"selectivity_for_columns": [
{
"column_name": "b",
"ranges": ["2 <= b <= 2"],
"selectivity_from_histogram": 0.2891
},
{
"column_name": "c",
"ranges": ["3 <= c <= 3"],
"selectivity_from_histogram": 0.2891
}
],
@@ -2091,10 +2096,12 @@ explain select * from t1 where a=1 and b=2 order by c limit 1 {
"selectivity_for_columns": [
{
"column_name": "a",
"ranges": ["1 <= a <= 1"],
"selectivity_from_histogram": 0.1797
},
{
"column_name": "b",
"ranges": ["2 <= b <= 2"],
"selectivity_from_histogram": 0.0156
}
],
@@ -3310,10 +3317,12 @@ explain select * from t1 where pk = 2 and a=5 and b=1 {
"selectivity_for_columns": [
{
"column_name": "a",
"ranges": ["5 <= a <= 5"],
"selectivity_from_histogram": 0.1
},
{
"column_name": "b",
"ranges": ["1 <= b <= 1"],
"selectivity_from_histogram": 0.1
}
],
@@ -8465,5 +8474,90 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
]
]
DROP TABLE t1,t2;
# End of 10.4 tests
#
# MDEV-22665: Print ranges in the optimizer trace created for non-indexed columns when
# optimizer_use_condition_selectivity >2
#
CREATE TABLE t1(a INT, b INT);
INSERT INTO t1 SELECT seq, seq from seq_1_to_100;
SET optimizer_trace=1;
ANALYZE TABLE t1 PERSISTENT FOR ALL;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
EXPLAIN EXTENDED SELECT * from t1 WHERE a between 1 and 5 and b <= 5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 100 0.22 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` between 1 and 5 and `test`.`t1`.`b` <= 5
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
[
[
{
"column_name": "a",
"ranges":
[
"1 <= a <= 5"
],
"selectivity_from_histogram": 0.0469
},
{
"column_name": "b",
"ranges":
[
"NULL < b <= 5"
],
"selectivity_from_histogram": 0.0469
}
]
]
EXPLAIN EXTENDED SELECT * from t1 WHERE a != 5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 100 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` <> 5
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
[
[
{
"column_name": "a",
"ranges":
[
"NULL < a < 5",
"5 < a"
],
"selectivity_from_histogram": 1
}
]
]
EXPLAIN EXTENDED SELECT * from t1 WHERE b >= 10 and b < 25;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 100 15.62 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`b` >= 10 and `test`.`t1`.`b` < 25
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
[
[
{
"column_name": "b",
"ranges":
[
"10 <= b < 25"
],
"selectivity_from_histogram": 0.1562
}
]
]
drop table t1;
set optimizer_trace='enabled=off';
# End of 10.4 tests

18
mysql-test/main/opt_trace.test
View File

@@ -594,6 +594,22 @@ EXPLAIN SELECT * FROM t1, t2 WHERE t1.a=t2.a ORDER BY t2.b;
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
DROP TABLE t1,t2;
--echo # End of 10.4 tests
--echo #
--echo # MDEV-22665: Print ranges in the optimizer trace created for non-indexed columns when
--echo # optimizer_use_condition_selectivity >2
--echo #
CREATE TABLE t1(a INT, b INT);
INSERT INTO t1 SELECT seq, seq from seq_1_to_100;
SET optimizer_trace=1;
ANALYZE TABLE t1 PERSISTENT FOR ALL;
EXPLAIN EXTENDED SELECT * from t1 WHERE a between 1 and 5 and b <= 5;
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
EXPLAIN EXTENDED SELECT * from t1 WHERE a != 5;
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
EXPLAIN EXTENDED SELECT * from t1 WHERE b >= 10 and b < 25;
select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
drop table t1;
set optimizer_trace='enabled=off';
--echo # End of 10.4 tests

40
sql/field.cc
View File

@@ -11400,6 +11400,46 @@ void Field_blob::print_key_value(String *out, uint32 length)
}
/*
@brief Print value of the key part
@param
out Output string
key value of the key
length Length of field in bytes,
excluding NULL flag and length bytes
*/
void
Field::print_key_part_value(String *out, const uchar* key, uint32 length)
{
StringBuffer<128> tmp(system_charset_info);
uint null_byte= 0;
if (real_maybe_null())
{
/*
Byte 0 of key is the null-byte. If set, key is NULL.
Otherwise, print the key value starting immediately after the
null-byte
*/
if (*key)
{
out->append(STRING_WITH_LEN("NULL"));
return;
}
null_byte++; // Skip null byte
}
set_key_image(key + null_byte, length);
print_key_value(&tmp, length);
if (charset() == &my_charset_bin)
out->append(tmp.ptr(), tmp.length(), tmp.charset());
else
tmp.print(out, system_charset_info);
}
void Field::print_key_value_binary(String *out, const uchar* key, uint32 length)
{
out->append_semi_hex((const char*)key, length, charset());

1
sql/field.h
View File

@@ -1410,6 +1410,7 @@ public:
bool set_warning(Sql_condition::enum_warning_level, unsigned int code,
int cuted_increment, ulong current_row=0) const;
virtual void print_key_value(String *out, uint32 length);
void print_key_part_value(String *out, const uchar *key, uint32 length);
void print_key_value_binary(String *out, const uchar* key, uint32 length);
protected:
bool set_warning(unsigned int code, int cuted_increment) const

123
sql/opt_range.cc
View File

@@ -442,6 +442,13 @@ static
void print_range(String *out, const KEY_PART_INFO *key_part,
KEY_MULTI_RANGE *range, uint n_key_parts);
static
void print_range_for_non_indexed_field(String *out, Field *field,
KEY_MULTI_RANGE *range);
static void print_min_range_operator(String *out, const ha_rkey_function flag);
static void print_max_range_operator(String *out, const ha_rkey_function flag);
/*
SEL_IMERGE is a list of possible ways to do index merge, i.e. it is
@@ -3174,6 +3181,7 @@ static
double records_in_column_ranges(PARAM *param, uint idx,
SEL_ARG *tree)
{
THD *thd= param->thd;
SEL_ARG_RANGE_SEQ seq;
KEY_MULTI_RANGE range;
range_seq_t seq_it;
@@ -3200,6 +3208,8 @@ double records_in_column_ranges(PARAM *param, uint idx,
seq_it= seq_if.init((void *) &seq, 0, flags);
Json_writer_array range_trace(thd, "ranges");
while (!seq_if.next(seq_it, &range))
{
key_range *min_endp, *max_endp;
@@ -3216,6 +3226,13 @@ double records_in_column_ranges(PARAM *param, uint idx,
if (range.start_key.flag == HA_READ_BEFORE_KEY)
range_flag |= NEAR_MAX;
if (unlikely(thd->trace_started()))
{
StringBuffer<128> range_info(system_charset_info);
print_range_for_non_indexed_field(&range_info, field, &range);
range_trace.add(range_info.c_ptr_safe(), range_info.length());
}
rows= get_column_range_cardinality(field, min_endp, max_endp, range_flag);
if (DBL_MAX == rows)
{
@@ -15804,6 +15821,37 @@ void QUICK_GROUP_MIN_MAX_SELECT::dbug_dump(int indent, bool verbose)
#endif /* !DBUG_OFF */
/*
@brief Print the comparison operator for the min range
*/
static void print_min_range_operator(String *out, const ha_rkey_function flag)
{
if (flag == HA_READ_AFTER_KEY)
out->append(STRING_WITH_LEN(" < "));
else if (flag == HA_READ_KEY_EXACT || flag == HA_READ_KEY_OR_NEXT)
out->append(STRING_WITH_LEN(" <= "));
else
out->append(STRING_WITH_LEN(" ? "));
}
/*
@brief Print the comparison operator for the max range
*/
static void print_max_range_operator(String *out, const ha_rkey_function flag)
{
if (flag == HA_READ_BEFORE_KEY)
out->append(STRING_WITH_LEN(" < "));
else if (flag == HA_READ_AFTER_KEY)
out->append(STRING_WITH_LEN(" <= "));
else
out->append(STRING_WITH_LEN(" ? "));
}
static
void print_range(String *out, const KEY_PART_INFO *key_part,
KEY_MULTI_RANGE *range, uint n_key_parts)
@@ -15832,30 +15880,55 @@ void print_range(String *out, const KEY_PART_INFO *key_part,
{
print_key_value(out, key_part, range->start_key.key,
range->start_key.length);
if (range->start_key.flag == HA_READ_AFTER_KEY)
out->append(STRING_WITH_LEN(" < "));
else if (range->start_key.flag == HA_READ_KEY_EXACT ||
range->start_key.flag == HA_READ_KEY_OR_NEXT)
out->append(STRING_WITH_LEN(" <= "));
else
out->append(STRING_WITH_LEN(" ? "));
print_min_range_operator(out, range->start_key.flag);
}
print_keyparts_name(out, key_part, n_key_parts, keypart_map);
if (range->end_key.length)
{
if (range->end_key.flag == HA_READ_BEFORE_KEY)
out->append(STRING_WITH_LEN(" < "));
else if (range->end_key.flag == HA_READ_AFTER_KEY)
out->append(STRING_WITH_LEN(" <= "));
else
out->append(STRING_WITH_LEN(" ? "));
print_max_range_operator(out, range->end_key.flag);
print_key_value(out, key_part, range->end_key.key,
range->end_key.length);
}
}
/*
@brief Print range created for non-indexed columns
@param
out output string
field field for which the range is printed
range range for the field
*/
static
void print_range_for_non_indexed_field(String *out, Field *field,
KEY_MULTI_RANGE *range)
{
TABLE *table= field->table;
my_bitmap_map *old_sets[2];
dbug_tmp_use_all_columns(table, old_sets, table->read_set, table->write_set);
if (range->start_key.length)
{
field->print_key_part_value(out, range->start_key.key, field->key_length());
print_min_range_operator(out, range->start_key.flag);
}
out->append(field->field_name);
if (range->end_key.length)
{
print_max_range_operator(out, range->end_key.flag);
field->print_key_part_value(out, range->end_key.key, field->key_length());
}
dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_sets);
}
/*
Add ranges to the trace
@@ -15927,30 +16000,8 @@ static void print_key_value(String *out, const KEY_PART_INFO *key_part,
field= key_part->field;
store_length= key_part->store_length;
if (field->real_maybe_null())
{
/*
Byte 0 of key is the null-byte. If set, key is NULL.
Otherwise, print the key value starting immediately after the
null-byte
*/
if (*key)
{
out->append(STRING_WITH_LEN("NULL"));
goto next;
}
key++; // Skip null byte
store_length--;
}
field->print_key_part_value(out, key, key_part->length);
field->set_key_image(key, key_part->length);
field->print_key_value(&tmp, key_part->length);
if (field->charset() == &my_charset_bin)
out->append(tmp.ptr(), tmp.length(), tmp.charset());
else
tmp.print(out, system_charset_info);
next:
if (key + store_length < key_end)
out->append(STRING_WITH_LEN(","));
}