MDEV-8646: Re-engineer the code for post-join operations

- Make EXPLAIN code use the post-join operations
- Remove Sort_and_group_tracker that was used for that purpose

1 files changed, 0 insertions, 171 deletions

diff --git a/sql/sql_analyze_stmt.h b/sql/sql_analyze_stmt.h
index d7634bdfb85..2a08a842dfc 100644
--- a/sql/sql_analyze_stmt.h
+++ b/sql/sql_analyze_stmt.h
@@ -284,174 +284,3 @@ private:
   ulonglong sort_buffer_size;
 };
 
-
-typedef enum 
-{
-  EXPL_NO_TMP_TABLE=0,
-  EXPL_TMP_TABLE_BUFFER,
-  EXPL_TMP_TABLE_GROUP,
-  EXPL_TMP_TABLE_DISTINCT
-} enum_tmp_table_use;
-
-
-typedef enum 
-{
-  EXPL_ACTION_EOF, /* not-an-action */
-  EXPL_ACTION_FILESORT,
-  EXPL_ACTION_TEMPTABLE,
-  EXPL_ACTION_REMOVE_DUPS,
-} enum_qep_action;
-
-
-/*
-  This is to track how a JOIN object has resolved ORDER/GROUP BY/DISTINCT
-  
-  We are not tied to the query plan at all, because query plan does not have 
-  sufficient information. *A lot* of decisions about ordering/grouping are 
-  made at very late stages (in JOIN::exec, JOIN::init_execution, in
-  create_sort_index and even in create_tmp_table).
-
-  The idea is that operations that happen during select execution will report
-  themselves. We have these operations:
-  - Sorting with filesort()
-  - Duplicate row removal (the one done by remove_duplicates()).
-  - Use of temporary table to buffer the result.
-
-  There is also "Selection" operation, done by do_select(). It reads rows,
-  there are several distinct cases:
-   1. doing the join operation on the base tables
-   2. reading the temporary table
-   3. reading the filesort output
-  it would be nice to build execution graph, e.g.
-
-    Select(JOIN op) -> temp.table -> filesort -> Select(filesort result)
-
-  the problem is that there is no way to tell what a do_select() call will do.
-
-  Our solution is not to have explicit selection operations. We make these
-  assumptions about the query plan:
-  - Select(JOIN op) is the first operation in the query plan
-  - Unless the first recorded operation is filesort(). filesort() is unable 
-    read result of a select, so when we find it first, the query plan is:
-
-    filesort(first join table) -> Select(JOIN op) -> ...
-
-  the other popular query plan is:
-
-    Select (JOIN op) -> temp.table -> filesort() -> ...
-
-///TODO: handle repeated execution with subselects!
-*/
-
-class Sort_and_group_tracker : public Sql_alloc
-{
-  enum { MAX_QEP_ACTIONS = 5 };
-
-  /* Query actions in the order they were made. */
-  enum_qep_action qep_actions[MAX_QEP_ACTIONS];
-  
-  /* Number for the next action */
-  int cur_action;
-
-  /*
-    Non-zero means there was already an execution which had
-    #total_actions actions
-  */
-  int total_actions;
-
-  int get_n_actions()
-  {
-    return total_actions? total_actions: cur_action;
-  }
-
-  /*
-    TRUE<=>there were executions which took different sort/buffer/de-duplicate
-    routes. The counter values are not meaningful.
-  */
-  bool varied_executions;
-
-  /* Details about query actions */
-  union 
-  {
-    Filesort_tracker *filesort_tracker;
-    enum_tmp_table_use tmp_table;
-  } 
-  qep_actions_data[MAX_QEP_ACTIONS];
-  
-  Filesort_tracker *dummy_fsort_tracker;
-  bool is_analyze;
-public:
-  Sort_and_group_tracker(bool is_analyze_arg) :
-    cur_action(0), total_actions(0), varied_executions(false),
-    dummy_fsort_tracker(NULL),
-    is_analyze(is_analyze_arg)
-  {}
-
-  /*************** Reporting interface ***************/
-  /* Report that join execution is started */
-  void report_join_start()
-  {
-    if (!total_actions && cur_action != 0)
-    {
-      /* This is a second execution */
-      total_actions= cur_action;
-    }
-    cur_action= 0;
-  }
-
-  /* 
-    Report that a temporary table is created. The next step is to write to the
-    this tmp. table
-  */
-  void report_tmp_table(TABLE *tbl);
-
-  /* 
-    Report that we are doing a filesort. 
-      @return 
-        Tracker object to be used with filesort
-  */
-  Filesort_tracker *report_sorting(THD *thd);
-  
-  /*
-    Report that remove_duplicates() is invoked [on a temp. table].
-    We don't collect any statistics on this operation, yet.
-  */
-  void report_duplicate_removal();
-  
-  friend class Iterator;
-  /*************** Statistics retrieval interface ***************/
-  bool had_varied_executions() { return varied_executions; }
-
-  class Iterator 
-  {
-    Sort_and_group_tracker *owner;
-    int idx;
-  public:
-    Iterator(Sort_and_group_tracker *owner_arg) : 
-      owner(owner_arg), idx(owner_arg->get_n_actions() - 1)
-    {}
-
-    enum_qep_action get_next(Filesort_tracker **tracker/*,
-                             enum_tmp_table_use *tmp_table_use*/)
-    {
-      /* Walk back through the array... */
-      if (idx < 0)
-        return EXPL_ACTION_EOF;
-      switch (owner->qep_actions[idx])
-      {
-        case EXPL_ACTION_FILESORT:
-          *tracker= owner->qep_actions_data[idx].filesort_tracker;
-          break;
-        case EXPL_ACTION_TEMPTABLE:
-          //*tmp_table_use= tmp_table_kind[tmp_table_idx++];
-          break;
-        default:
-          break;
-      }
-      return owner->qep_actions[idx--];
-    }
-
-    bool is_last_element() { return idx == -1; }
-  };
-};
-