Adding "virtual bool Field::can_optimize_range(...)" and moving the code

from Item_bool_func::get_mm_leaf() into Field_xxx::can_optimize_range(). This reduces the total amount of virtual calls. Also, it's a prerequisite change for the pluggable data types.

Author: Alexander Barkov

sql/field.cc

@@ -1309,6 +1309,19 @@ bool Field::can_optimize_group_min_max(const Item_bool_func *cond,
 }
 
 
+/*
+ This covers all numeric types, ENUM, SET, BIT
+*/
+bool Field::can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const
+{
+ DBUG_ASSERT(cmp_type() != TIME_RESULT); // Handled in Field_temporal
+ DBUG_ASSERT(cmp_type() != STRING_RESULT); // Handled in Field_longstr
+ return item->cmp_type() != TIME_RESULT;
+}
+
+
 /**
  Numeric fields base class constructor.
 */
@@ -6955,6 +6968,16 @@ bool Field_longstr::can_optimize_group_min_max(const Item_bool_func *cond,
 }
 
 
+bool Field_longstr::can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const
+{
+ return is_eq_func ?
+ cmp_to_string_with_stricter_collation(cond, item) :
+ cmp_to_string_with_same_collation(cond, item);
+}
+
+
 /**
  This overrides the default behavior of the parent constructor
  Warn_filter(thd) to suppress notes about trailing spaces in case of CHAR(N),
@@ -8461,6 +8484,14 @@ Field::geometry_type Field_geom::geometry_type_merge(geometry_type a,
  return Field::GEOM_GEOMETRY;
 }
 
+
+bool Field_geom::can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const
+{
+ return item->cmp_type() == STRING_RESULT;
+}
+
 #endif /*HAVE_SPATIAL*/
 
 /****************************************************************************

sql/field.h

@@ -1199,16 +1199,6 @@ class Field: public Value_source
  { return binary() ? &my_charset_bin : charset(); }
  virtual CHARSET_INFO *sort_charset(void) const { return charset(); }
  virtual bool has_charset(void) const { return FALSE; }
- /*
- match_collation_to_optimize_range() is to distinguish in
- range optimizer (see opt_range.cc) between real string types:
- CHAR, VARCHAR, TEXT
- and the other string-alike types with result_type() == STRING_RESULT:
- DATE, TIME, DATETIME, TIMESTAMP
- We need it to decide whether to test if collation of the operation
- matches collation of the field (needed only for real string types).
- */
- virtual bool match_collation_to_optimize_range() const { return false; }
  virtual void set_charset(CHARSET_INFO *charset_arg) { }
  virtual enum Derivation derivation(void) const
  { return DERIVATION_IMPLICIT; }
@@ -1359,6 +1349,15 @@ class Field: public Value_source
  }
  virtual bool can_optimize_group_min_max(const Item_bool_func *cond,
  const Item *const_item) const;
+ /**
+ Test if Field can use range optimizer for a standard comparison operation:
+ <=, <, =, <=>, >, >=
+ Note, this method does not cover spatial operations.
+ */
+ virtual bool can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const;
+
  bool can_optimize_outer_join_table_elimination(const Item_bool_func *cond,
  const Item *item) const
  {
@@ -1583,13 +1582,15 @@ class Field_longstr :public Field_str
 
  int store_decimal(const my_decimal *d);
  uint32 max_data_length() const;
- bool match_collation_to_optimize_range() const { return true; }
  bool can_optimize_keypart_ref(const Item_bool_func *cond,
  const Item *item) const;
  bool can_optimize_hash_join(const Item_bool_func *cond,
  const Item *item) const;
  bool can_optimize_group_min_max(const Item_bool_func *cond,
  const Item *const_item) const;
+ bool can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const;
 };
 
 /* base class for float and double and decimal (old one) */
@@ -2082,6 +2083,12 @@ class Field_temporal: public Field {
  const Item *item) const;
  bool can_optimize_group_min_max(const Item_bool_func *cond,
  const Item *const_item) const;
+ bool can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const
+ {
+ return true;
+ }
 };
 
 
@@ -3101,7 +3108,9 @@ class Field_geom :public Field_blob {
  { geom_type= geom_type_arg; srid= 0; }
  enum ha_base_keytype key_type() const { return HA_KEYTYPE_VARBINARY2; }
  enum_field_types type() const { return MYSQL_TYPE_GEOMETRY; }
- bool match_collation_to_optimize_range() const { return false; }
+ bool can_optimize_range(const Item_bool_func *cond,
+ const Item *item,
+ bool is_eq_func) const;
  void sql_type(String &str) const;
  int store(const char *to, uint length, CHARSET_INFO *charset);
  int store(double nr);

sql/opt_range.cc

@@ -7849,41 +7849,17 @@ Item_bool_func::get_mm_leaf(RANGE_OPT_PARAM *param,
  if (key_part->image_type != Field::itRAW)
  DBUG_RETURN(0); // e.g. SPATIAL index
 
- /*
- 1. Usually we can't use an index if the column collation
- differ from the operation collation.
-
- 2. However, we can reuse a case insensitive index for
- the binary searches:
-
- WHERE latin1_swedish_ci_column = 'a' COLLATE lati1_bin;
-
- WHERE latin1_swedish_ci_colimn = BINARY 'a '
-
- */
- if (field->result_type() == STRING_RESULT &&
- field->match_collation_to_optimize_range() &&
- value->result_type() == STRING_RESULT &&
- field->charset() != compare_collation() &&
- !((type == EQUAL_FUNC || type == EQ_FUNC) &&
- compare_collation()->state & MY_CS_BINSORT))
- goto end;
- if (value->cmp_type() == TIME_RESULT && field->cmp_type() != TIME_RESULT)
- goto end;
-
  if (param->using_real_indexes &&
  !field->optimize_range(param->real_keynr[key_part->key],
  key_part->part) &&
  type != EQ_FUNC &&
  type != EQUAL_FUNC)
  goto end; // Can't optimize this
 
- /*
- We can't always use indexes when comparing a string index to a number
- cmp_type() is checked to allow compare of dates to numbers
- */
- if (field->cmp_type() == STRING_RESULT && value->cmp_type() != STRING_RESULT)
+ if (!field->can_optimize_range(this, value,
+ type == EQUAL_FUNC || type == EQ_FUNC))
  goto end;
+
  err= value->save_in_field_no_warnings(field, 1);
  if (err == 2 && field->cmp_type() == STRING_RESULT)
  {