index_range_scan_plan.h

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#ifndef SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_
#define SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_
 
#include <sys/types.h>
 
#include "my_dbug.h"
#include "sql/handler.h"
#include "sql/range_optimizer/geometry_index_range_scan.h"
#include "sql/range_optimizer/index_range_scan.h"
#include "sql/range_optimizer/range_opt_param.h"
#include "sql/range_optimizer/range_optimizer.h"
#include "sql/range_optimizer/reverse_index_range_scan.h"
#include "sql/sql_const.h"
 
class Opt_trace_object;
class RANGE_OPT_PARAM;
class SEL_ROOT;
class SEL_TREE;
struct MEM_ROOT;
 
bool get_ranges_from_tree(MEM_ROOT *return_mem_root, TABLE *table,
                          KEY_PART *key, uint keyno, SEL_ROOT *key_tree,
                          uint num_key_parts, unsigned *used_key_parts,
                          unsigned *num_exact_key_parts, Quick_ranges *ranges);
 
/*
  Get best "range" table read plan for given SEL_TREE, also update some info
 
  SYNOPSIS
    get_key_scans_params()
      param                    Parameters from test_quick_select
      tree                     Make range select for this SEL_TREE
      index_read_must_be_used  true <=> assume 'index only' option will be set
                               (except for clustered PK indexes)
      update_tbl_stats         true <=> update table->quick_* with information
                               about range scans we've evaluated.
      interesting_order        The sort order the range access method must be
                               able to provide. Three-value logic:
                               asc/desc/don't care
      skip_records_in_range    Same value as JOIN_TAB::skip_records_in_range().
      cost_est                 Maximum cost. i.e. don't create read plans with
                               cost > cost_est.
      ror_only                 true <=> consider only ROR scans.
      needed_reg               ptr to needed_reg argument
                               of test_quick_select().
 
  DESCRIPTION
    Find the best "range" table read plan for given SEL_TREE.
    The side effects are
     - tree->ror_scans is updated to indicate which scans are ROR scans.
     - if update_tbl_stats=true then table->quick_* is updated with info
       about every possible range scan.
 
  RETURN
    Best range read plan
    NULL if no plan found or error occurred
*/
 
AccessPath *get_key_scans_params(THD *thd, RANGE_OPT_PARAM *param,
                                 SEL_TREE *tree, bool index_read_must_be_used,
                                 bool update_tbl_stats,
                                 enum_order interesting_order,
                                 bool skip_records_in_range, double cost_est,
                                 bool ror_only, Key_map *needed_reg);
 
/*
  Calculate estimate of number records that will be retrieved by a range
  scan on given index using given SEL_ARG intervals tree.
 
  SYNOPSIS
    check_quick_select()
      param             Parameter from test_quick_select
      idx               Number of index to use in RANGE_OPT_PARAM::key
                        SEL_TREE::key
      index_only        true  - assume only index tuples will be accessed
                        false - assume full table rows will be read
      tree              Transformed selection condition, tree->key[idx] holds
                        the intervals for the given index.
      update_tbl_stats  true <=> update table->quick_* with information
                        about range scan we've evaluated.
      order_direction   The sort order the range access method must be able
                        to provide. Three-value logic: asc/desc/don't care
      skip_records_in_range Same value as JOIN_TAB::skip_records_in_range().
      mrr_flags   INOUT MRR access flags
      cost        OUT   Scan cost
      is_ror_scan OUT   Set to reflect if the key scan is a ROR
                        (see is_key_scan_ror function for more info)
      is_imerge_scan OUT  Set to reflect if the key scan can be used for
                        index-merge-scan
 
  NOTES
    param->table->quick_*, param->range_count (and maybe others) are
    updated with data of given key scan, see quick_range_seq_next for details.
 
  RETURN
    Estimate # of records to be retrieved.
    HA_POS_ERROR if estimate calculation failed due to table handler problems.
*/
ha_rows check_quick_select(THD *thd, RANGE_OPT_PARAM *param, uint idx,
                           bool index_only, SEL_ROOT *tree,
                           bool update_tbl_stats, enum_order order_direction,
                           bool skip_records_in_range, uint *mrr_flags,
                           uint *bufsize, Cost_estimate *cost,
                           bool *is_ror_scan, bool *is_imerge_scan);
 
#ifndef NDEBUG
void dbug_dump_range(int indent, bool verbose, TABLE *table, int index,
                     KEY_PART *used_key_part,
                     Bounds_checked_array<QUICK_RANGE *> ranges);
#endif
 
void trace_basic_info_index_range_scan(THD *thd, const AccessPath *path,
                                       const RANGE_OPT_PARAM *param,
                                       Opt_trace_object *trace_object);
 
#endif  // SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_