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Merging index_merge/Unique into 5.0

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This commit is contained in:
sergefp@mysql.com
2003-11-23 15:17:46 +03:00
parent c8bc4edc7f 1c61a92ba7
commit 5f9718adfb
7 changed files with 116 additions and 273 deletions
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80
sql/opt_range.h
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@ -65,7 +65,6 @@ class QUICK_RANGE :public Sql_alloc {
}
};
class INDEX_MERGE;
/*
Quick select interface.
@ -149,64 +148,6 @@ public:
int get_type() { return QS_TYPE_RANGE; }
};
/*
Helper class for keeping track of rows that have been passed to output
in index_merge access method.
NOTES
Current implementation uses a temporary table to store ROWIDs of rows that
have been passed to output. In the future it might be changed to use more
efficient mechanisms, like Unique class.
*/
class INDEX_MERGE
{
public:
INDEX_MERGE(THD *thd_arg);
~INDEX_MERGE();
int init(TABLE *table);
int check_record_in();
int start_last_quick_select();
int error;
private:
/* The only field in temporary table */
class Item_rowid : public Item_str_func
{
TABLE *head; /* source table */
public:
Item_rowid(TABLE *table) : head(table)
{
max_length= table->file->ref_length;
collation.set(&my_charset_bin);
};
const char *func_name() const { return "rowid"; }
bool const_item() const { return 0; }
String *val_str(String *);
void fix_length_and_dec()
{}
};
/* Check if record has been processed and save it if it wasn't */
inline int put_record();
/* Check if record has been processed without saving it */
inline int check_record();
/* If true, check_record_in does't store ROWIDs it is passed. */
bool dont_save;
THD *thd;
TABLE *head; /* source table */
TABLE *temp_table; /* temp. table used for values storage */
TMP_TABLE_PARAM tmp_table_param; /* temp. table creation parameters */
Item_rowid *rowid_item; /* the only field in temp. table */
List<Item> fields; /* temp. table fields list
(the only element is rowid_item) */
ORDER order; /* key for temp. table (rowid_item) */
};
/*
Index merge quick select.
It is implemented as a container for several QUICK_RANGE_SELECTs.
@ -219,7 +160,7 @@ public:
~QUICK_INDEX_MERGE_SELECT();
int init();
void reset(void);
int reset(void);
int get_next();
bool reverse_sorted() { return false; }
bool unique_key_range() { return false; }
@ -234,20 +175,15 @@ public:
List_iterator_fast<QUICK_RANGE_SELECT> cur_quick_it;
QUICK_RANGE_SELECT* cur_quick_select;
/*
Last element in quick_selects list.
INDEX_MERGE::start_last_quick_select is called before retrieving
rows for it.
*/
/* last element in quick_selects list. */
QUICK_RANGE_SELECT* last_quick_select;
/*
Used to keep track of what records have been already passed to output
when doing index_merge access (NULL means no index_merge)
*/
INDEX_MERGE index_merge;
Unique *unique;
MEM_ROOT alloc;
MEM_ROOT alloc;
THD *thd;
int prepare_unique();
bool reset_called;
};
class QUICK_SELECT_DESC: public QUICK_RANGE_SELECT
@ -263,7 +199,7 @@ private:
#ifdef NOT_USED
bool test_if_null_range(QUICK_RANGE *range, uint used_key_parts);
#endif
void reset(void) { next=0; rev_it.rewind(); }
int reset(void) { next=0; rev_it.rewind(); return 0; }
List<QUICK_RANGE> rev_ranges;
List_iterator<QUICK_RANGE> rev_it;
};