diff options
Diffstat (limited to 'sql/opt_sum.cc')
| -rw-r--r-- | sql/opt_sum.cc | 79 |
1 files changed, 54 insertions, 25 deletions
diff --git a/sql/opt_sum.cc b/sql/opt_sum.cc index 1e116518da0..b96c6383bbb 100644 --- a/sql/opt_sum.cc +++ b/sql/opt_sum.cc @@ -69,8 +69,10 @@ static int maxmin_in_range(bool max_fl, Field* field, COND *cond); RETURN VALUES 0 No errors - 1 if all items was resolved - -1 on impossible conditions + 1 if all items were resolved + -1 on impossible conditions + OR an error number from my_base.h HA_ERR_... if a deadlock or a lock + wait timeout happens, for example */ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) @@ -82,6 +84,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) table_map where_tables= 0; Item *item; COND *org_conds= conds; + int error; if (conds) where_tables= conds->used_tables(); @@ -131,7 +134,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) if (outer_tables || (table->table->file->table_flags() & HA_NOT_EXACT_COUNT)) { - const_result= 0; // Can't optimize left join + const_result= 0; // Can't optimize left join break; } tables->table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK); @@ -164,6 +167,11 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) Item_field *item_field= ((Item_field*) expr); TABLE *table= item_field->field->table; + if ((table->file->table_flags() & HA_NOT_READ_AFTER_KEY)) + { + const_result=0; + break; + } /* Look for a partial key that can be used for optimization. If we succeed, ref.key_length will contain the length of @@ -179,18 +187,21 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) const_result= 0; break; } - bool error= table->file->index_init((uint) ref.key); + error= table->file->index_init((uint) ref.key); if (!ref.key_length) - error= table->file->index_first(table->record[0]) != 0; + error= table->file->index_first(table->record[0]); else - error= table->file->index_read(table->record[0],key_buff, - ref.key_length, - range_fl & NEAR_MIN ? - HA_READ_AFTER_KEY : - HA_READ_KEY_OR_NEXT) || - reckey_in_range(0, &ref, item_field->field, - conds, range_fl, prefix_len); + { + error= table->file->index_read(table->record[0],key_buff, + ref.key_length, + range_fl & NEAR_MIN ? + HA_READ_AFTER_KEY : + HA_READ_KEY_OR_NEXT); + if (!error && reckey_in_range(0, &ref, item_field->field, + conds, range_fl, prefix_len)) + error= HA_ERR_KEY_NOT_FOUND; + } if (table->key_read) { table->key_read= 0; @@ -198,10 +209,16 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) } table->file->index_end(); if (error) - return -1; // No rows matching where + { + if (error == HA_ERR_KEY_NOT_FOUND || error == HA_ERR_END_OF_FILE) + return -1; // No rows matching WHERE + /* HA_ERR_LOCK_DEADLOCK or some other error */ + table->file->print_error(error, MYF(0)); + return(error); + } removed_tables|= table->map; } - else if (!expr->const_item()) // This is VERY seldom false + else if (!expr->const_item()) // This is VERY seldom false { const_result= 0; break; @@ -249,18 +266,20 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) const_result= 0; break; } - bool error= table->file->index_init((uint) ref.key); + error= table->file->index_init((uint) ref.key); if (!ref.key_length) - error=table->file->index_last(table->record[0]) != 0; + error= table->file->index_last(table->record[0]); else - error= table->file->index_read(table->record[0], key_buff, - ref.key_length, - range_fl & NEAR_MAX ? - HA_READ_BEFORE_KEY : - HA_READ_PREFIX_LAST_OR_PREV) || - reckey_in_range(1, &ref, item_field->field, - conds, range_fl, prefix_len); + { + error= table->file->index_read(table->record[0], key_buff, + ref.key_length, + range_fl & NEAR_MAX ? + HA_READ_BEFORE_KEY : + HA_READ_PREFIX_LAST_OR_PREV); + if (!error && reckey_in_range(1, &ref, item_field->field, + conds, range_fl, prefix_len)) + error= HA_ERR_KEY_NOT_FOUND; if (table->key_read) { table->key_read=0; @@ -268,10 +287,16 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) } table->file->index_end(); if (error) - return -1; // Impossible query + { + if (error == HA_ERR_KEY_NOT_FOUND || error == HA_ERR_END_OF_FILE) + return -1; // No rows matching WHERE + /* HA_ERR_LOCK_DEADLOCK or some other error */ + table->file->print_error(error, MYF(0)); + return(error); + } removed_tables|= table->map; } - else if (!expr->const_item()) // This is VERY seldom false + else if (!expr->const_item()) // This is VERY seldom false { const_result= 0; break; @@ -597,6 +622,10 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo, (if we have a condition field = const, prefix_len contains the length of the whole search key) + NOTE + This function may set table->key_read to 1, which must be reset after + index is used! (This can only happen when function returns 1) + RETURN 0 Index can not be used to optimize MIN(field)/MAX(field) 1 Can use key to optimize MIN()/MAX() |