group_index_skip_scan_plan.h

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#ifndef SQL_RANGE_OPTIMIZER_GROUP_INDEX_SKIP_SCAN_PLAN_H_
#define SQL_RANGE_OPTIMIZER_GROUP_INDEX_SKIP_SCAN_PLAN_H_
 
#include <sys/types.h>
 
#include "my_base.h"
#include "my_inttypes.h"
#include "sql/range_optimizer/range_optimizer.h"
#include "sql/sql_const.h"
 
class KEY;
class KEY_PART_INFO;
class Opt_trace_object;
class RANGE_OPT_PARAM;
class SEL_ROOT;
class SEL_TREE;
 
/*
  Plan for a GroupIndexSkipScanIterator scan.
*/
 
struct GroupIndexSkipScanParameters {
  Mem_root_array<Item_sum *> min_functions;
  Mem_root_array<Item_sum *> max_functions;
  /**
    true if there is an aggregate distinct function, e.g.
    "COUNT(DISTINCT x)"
  */
  bool have_agg_distinct;
  /**
    The key_part of the only field used by all MIN/MAX functions.
    Note that GROUP_INDEX_SKIP_SCAN is not used if there are MIN/MAX
    functions on more than one field.
  */
  KEY_PART_INFO *min_max_arg_part;
  uint group_prefix_len;  ///< Length of all key parts in the group prefix
  uint group_key_parts;   ///< Number of index key parts in the group prefix
  KEY *index_info;        ///< The index chosen for data access
  uint key_infix_len;     ///< Longest key for equality predicates
  SEL_ROOT
  *index_tree_tracing_only;  ///< The sub-tree corresponding to index_info
  bool is_index_scan;        ///< Use index_next() instead of random read
  KEY_PART *used_key_part;
  uint real_key_parts;
  uint max_used_key_length;
  Quick_ranges prefix_ranges;
  Quick_ranges_array key_infix_ranges;
  Quick_ranges min_max_ranges;
};
 
AccessPath *get_best_group_min_max(THD *thd, RANGE_OPT_PARAM *param,
                                   SEL_TREE *tree, enum_order order_direction,
                                   bool skip_records_in_range, double cost_est);
 
void trace_basic_info_group_index_skip_scan(THD *thd, const AccessPath *path,
                                            const RANGE_OPT_PARAM *,
                                            Opt_trace_object *trace_object);
 
void dbug_dump_group_index_skip_scan(int indent, bool verbose,
                                     const AccessPath *path);
 
#endif  // SQL_RANGE_OPTIMIZER_GROUP_INDEX_SKIP_SCAN_PLAN_H_