diff options
| -rw-r--r-- | sql/sql_select.cc | 14 | ||||
| -rw-r--r-- | sql/sql_show.cc | 1 | ||||
| -rw-r--r-- | sql/sql_show.h | 10 |
3 files changed, 19 insertions, 6 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 05c88a5f534..1fedf12b595 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -23490,16 +23490,19 @@ void JOIN_TAB::save_explain_data(Explain_table_access *eta, table_map prefix_tab const char *tmp_buff; int f_idx; StringBuffer<64> key_name_buf; - if (is_table_read_plan->has_db_lookup_value()) + if (is_table_read_plan->trivial_show_command || + is_table_read_plan->has_db_lookup_value()) { /* The "key" has the name of the column referring to the database */ f_idx= table_list->schema_table->idx_field1; tmp_buff= table_list->schema_table->fields_info[f_idx].field_name; key_name_buf.append(tmp_buff, strlen(tmp_buff), cs); } - if (is_table_read_plan->has_table_lookup_value()) + if (is_table_read_plan->trivial_show_command || + is_table_read_plan->has_table_lookup_value()) { - if (is_table_read_plan->has_db_lookup_value()) + if (is_table_read_plan->trivial_show_command || + is_table_read_plan->has_db_lookup_value()) key_name_buf.append(','); f_idx= table_list->schema_table->idx_field2; @@ -23630,8 +23633,9 @@ void JOIN_TAB::save_explain_data(Explain_table_access *eta, table_map prefix_tab else eta->push_extra(ET_OPEN_FULL_TABLE); /* psergey-note: the following has a bug.*/ - if (table_list->is_table_read_plan->has_db_lookup_value() && - table_list->is_table_read_plan->has_table_lookup_value()) + if (table_list->is_table_read_plan->trivial_show_command || + (table_list->is_table_read_plan->has_db_lookup_value() && + table_list->is_table_read_plan->has_table_lookup_value())) eta->push_extra(ET_SCANNED_0_DATABASES); else if (table_list->is_table_read_plan->has_db_lookup_value() || table_list->is_table_read_plan->has_table_lookup_value()) diff --git a/sql/sql_show.cc b/sql/sql_show.cc index bb8ae16189a..ec7d4979a4e 100644 --- a/sql/sql_show.cc +++ b/sql/sql_show.cc @@ -8035,6 +8035,7 @@ static bool optimize_for_get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond if (lsel && lsel->table_list.first) { /* These do not need to have a query plan */ + plan->trivial_show_command= true; goto end; } diff --git a/sql/sql_show.h b/sql/sql_show.h index 2f1cb26d17a..2b58fc45d4c 100644 --- a/sql/sql_show.h +++ b/sql/sql_show.h @@ -192,9 +192,17 @@ typedef struct st_lookup_field_values class IS_table_read_plan : public Sql_alloc { public: - IS_table_read_plan() : no_rows(false) {} + IS_table_read_plan() : no_rows(false), trivial_show_command(FALSE) {} bool no_rows; + /* + For EXPLAIN only: For SHOW KEYS and SHOW COLUMNS, we know which + db_name.table_name will be read, however for some reason we don't + set the fields in this->lookup_field_vals. + In order to not have JOIN::save_explain_data() walking over uninitialized + data, we set trivial_show_command=true. + */ + bool trivial_show_command; LOOKUP_FIELD_VALUES lookup_field_vals; Item *partial_cond; |