MDEV-22665: Print ranges in the optimizer trace created for non-indexed...

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

Now the optimizer trace shows the ranges constructed while getting estimates from EITS

mysql-test/main/opt_trace.result

@@ -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

mysql-test/main/opt_trace.test

@@ -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

sql/field.cc

@@ -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());

sql/field.h

@@ -1410,6 +1410,7 @@ class Field: public Value_source
   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

sql/opt_range.cc

@@ -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->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);
+    field->print_key_part_value(out, key, key_part->length);
 
-  next:
     if (key + store_length < key_end)
       out->append(STRING_WITH_LEN(","));
   }