Commit da838339 authored by unknown's avatar unknown
Browse files

InnoDB: Optimize [and clarify] a condition in build_template() 


sql/ha_innodb.cc:
  build_template(): Optimize (and make more readable) the conditions
  for skipping or including a field.
parent 85036af7

sql/ha_innodb.cc

+32 −9
Original line number Diff line number Diff line
@@ -2955,21 +2955,44 @@ build_template( 
		templ = prebuilt->mysql_template + n_requested_fields;

		field = table->field[i];



                ibool index_contains_field=

		if (UNIV_LIKELY(templ_type == ROW_MYSQL_REC_FIELDS)) {

			/* Decide which columns we should fetch

			and which we can skip. */

			register const ibool	index_contains_field =

				dict_index_contains_col_or_prefix(index, i);



		if (templ_type == ROW_MYSQL_REC_FIELDS && 

                    ((prebuilt->read_just_key && !index_contains_field) ||

		     (!(fetch_all_in_key && index_contains_field) &&

		      !(fetch_primary_key_cols &&

			dict_table_col_in_clustered_key(index->table, i)) &&

		      thd->query_id != field->query_id))) {

			if (!index_contains_field && prebuilt->read_just_key) {

				/* If this is a 'key read', we do not need

				columns that are not in the key */



				goto skip_field;

			}



			if (index_contains_field && fetch_all_in_key) {

				/* This field is needed in the query */



				goto include_field;

			}



			if (thd->query_id == field->query_id) {

				/* This field is needed in the query */



				goto include_field;

			}



			if (fetch_primary_key_cols

			    && dict_table_col_in_clustered_key(index->table,

									i)) {

				/* This field is needed in the query */



				goto include_field;

			}



			/* This field is not needed in the query, skip it */



			goto skip_field;

		}



include_field:

		n_requested_fields++;



		templ->col_no = i;