diff options
Diffstat (limited to 'sql/opt_range.cc')
| -rw-r--r-- | sql/opt_range.cc | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/sql/opt_range.cc b/sql/opt_range.cc index d101b2fe91b..5cadd26da6e 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -133,7 +133,12 @@ static int sel_cmp(Field *f,uchar *a,uchar *b,uint8 a_flag,uint8 b_flag); -static uchar is_null_string[2]= {1,0}; +/* + this should be long enough so that any memcmp with a string that + starts from '\0' won't cross is_null_string boundaries, even + if the memcmp is optimized to compare 4- 8- or 16- bytes at once +*/ +static uchar is_null_string[20]= {1,0}; class RANGE_OPT_PARAM; /* @@ -2001,7 +2006,7 @@ int QUICK_ROR_INTERSECT_SELECT::init() 1 error */ -int QUICK_RANGE_SELECT::init_ror_merged_scan(bool reuse_handler) +int QUICK_RANGE_SELECT::init_ror_merged_scan(bool reuse_handler, MEM_ROOT *alloc) { handler *save_file= file, *org_file; my_bool org_key_read; @@ -2029,7 +2034,7 @@ int QUICK_RANGE_SELECT::init_ror_merged_scan(bool reuse_handler) DBUG_RETURN(0); } - if (!(file= head->file->clone(head->s->normalized_path.str, thd->mem_root))) + if (!(file= head->file->clone(head->s->normalized_path.str, alloc))) { /* Manually set the error flag. Note: there seems to be quite a few @@ -2130,7 +2135,8 @@ failure: 0 OK other error code */ -int QUICK_ROR_INTERSECT_SELECT::init_ror_merged_scan(bool reuse_handler) +int QUICK_ROR_INTERSECT_SELECT::init_ror_merged_scan(bool reuse_handler, + MEM_ROOT *alloc) { List_iterator_fast<QUICK_SELECT_WITH_RECORD> quick_it(quick_selects); QUICK_SELECT_WITH_RECORD *cur; @@ -2147,7 +2153,7 @@ int QUICK_ROR_INTERSECT_SELECT::init_ror_merged_scan(bool reuse_handler) There is no use of this->file. Use it for the first of merged range selects. */ - int error= quick->init_ror_merged_scan(TRUE); + int error= quick->init_ror_merged_scan(TRUE, alloc); if (error) DBUG_RETURN(error); quick->file->extra(HA_EXTRA_KEYREAD_PRESERVE_FIELDS); @@ -2159,7 +2165,7 @@ int QUICK_ROR_INTERSECT_SELECT::init_ror_merged_scan(bool reuse_handler) const MY_BITMAP * const save_read_set= quick->head->read_set; const MY_BITMAP * const save_write_set= quick->head->write_set; #endif - if (quick->init_ror_merged_scan(FALSE)) + if (quick->init_ror_merged_scan(FALSE, alloc)) DBUG_RETURN(1); quick->file->extra(HA_EXTRA_KEYREAD_PRESERVE_FIELDS); @@ -2193,7 +2199,7 @@ int QUICK_ROR_INTERSECT_SELECT::init_ror_merged_scan(bool reuse_handler) int QUICK_ROR_INTERSECT_SELECT::reset() { DBUG_ENTER("QUICK_ROR_INTERSECT_SELECT::reset"); - if (!scans_inited && init_ror_merged_scan(TRUE)) + if (!scans_inited && init_ror_merged_scan(TRUE, &alloc)) DBUG_RETURN(1); scans_inited= TRUE; List_iterator_fast<QUICK_SELECT_WITH_RECORD> it(quick_selects); @@ -2330,7 +2336,7 @@ int QUICK_ROR_UNION_SELECT::reset() List_iterator_fast<QUICK_SELECT_I> it(quick_selects); while ((quick= it++)) { - if (quick->init_ror_merged_scan(FALSE)) + if (quick->init_ror_merged_scan(FALSE, &alloc)) DBUG_RETURN(1); } scans_inited= TRUE; @@ -7622,8 +7628,10 @@ static SEL_TREE *get_mm_tree(RANGE_OPT_PARAM *param,COND *cond) DBUG_RETURN(tree); } /* Here when simple cond */ - if (cond->const_item() && !cond->is_expensive()) + if (cond->const_item()) { + if (cond->is_expensive()) + DBUG_RETURN(0); /* During the cond->val_int() evaluation we can come across a subselect item which may allocate memory on the thd->mem_root and assumes |