diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 3d2f7013a35..f42b9d9ee0e 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -3667,6 +3667,11 @@ int st_select_lex_unit::print_explain(select_result_sink *output) if ((res= sl->print_explain(output))) break; } + if (!fake_select_lex->join) + { + res= print_fake_select_lex_join(output, TRUE /* on the fly */, + fake_select_lex, 0 /* flags */); + } return res; } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 1d2c8a10b75..ee06ce0c8a6 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -20425,6 +20425,83 @@ void JOIN::clear() } } +int print_fake_select_lex_join(select_result_sink *result, bool on_the_fly, + SELECT_LEX *select_lex, uint8 select_options) +{ + const CHARSET_INFO *cs= system_charset_info; + Item *item_null= new Item_null(); + List item_list; + if (on_the_fly) + select_lex->set_explain_type(on_the_fly); //psergey + /* + here we assume that the query will return at least two rows, so we + show "filesort" in EXPLAIN. Of course, sometimes we'll be wrong + and no filesort will be actually done, but executing all selects in + the UNION to provide precise EXPLAIN information will hardly be + appreciated :) + */ + char table_name_buffer[SAFE_NAME_LEN]; + item_list.empty(); + /* id */ + item_list.push_back(new Item_null); + /* select_type */ + item_list.push_back(new Item_string(select_lex->type, + strlen(select_lex->type), + cs)); + /* table */ + { + SELECT_LEX *sl= select_lex->master_unit()->first_select(); + uint len= 6, lastop= 0; + memcpy(table_name_buffer, STRING_WITH_LEN("next_select()) + { + len+= lastop; + lastop= my_snprintf(table_name_buffer + len, NAME_LEN - len, + "%u,", sl->select_number); + } + if (sl || len + lastop >= NAME_LEN) + { + memcpy(table_name_buffer + len, STRING_WITH_LEN("...>") + 1); + len+= 4; + } + else + { + len+= lastop; + table_name_buffer[len - 1]= '>'; // change ',' to '>' + } + item_list.push_back(new Item_string(table_name_buffer, len, cs)); + } + /* partitions */ + if (/*join->thd->lex->describe*/ select_options & DESCRIBE_PARTITIONS) + item_list.push_back(item_null); + /* type */ + item_list.push_back(new Item_string(join_type_str[JT_ALL], + strlen(join_type_str[JT_ALL]), + cs)); + /* possible_keys */ + item_list.push_back(item_null); + /* key*/ + item_list.push_back(item_null); + /* key_len */ + item_list.push_back(item_null); + /* ref */ + item_list.push_back(item_null); + /* in_rows */ + if (select_options & DESCRIBE_EXTENDED) + item_list.push_back(item_null); + /* rows */ + item_list.push_back(item_null); + /* extra */ + if (select_lex->master_unit()->global_parameters->order_list.first) + item_list.push_back(new Item_string("Using filesort", + 14, cs)); + else + item_list.push_back(new Item_string("", 0, cs)); + + if (result->send_data(item_list)) + return 1; + return 0; +} /** EXPLAIN handling. @@ -20483,74 +20560,9 @@ int JOIN::print_explain(select_result_sink *result, bool on_the_fly, } else if (join->select_lex == join->unit->fake_select_lex) { - if (on_the_fly) - join->select_lex->set_explain_type(on_the_fly); //psergey - /* - here we assume that the query will return at least two rows, so we - show "filesort" in EXPLAIN. Of course, sometimes we'll be wrong - and no filesort will be actually done, but executing all selects in - the UNION to provide precise EXPLAIN information will hardly be - appreciated :) - */ - char table_name_buffer[SAFE_NAME_LEN]; - item_list.empty(); - /* id */ - item_list.push_back(new Item_null); - /* select_type */ - item_list.push_back(new Item_string(join->select_lex->type, - strlen(join->select_lex->type), - cs)); - /* table */ - { - SELECT_LEX *sl= join->unit->first_select(); - uint len= 6, lastop= 0; - memcpy(table_name_buffer, STRING_WITH_LEN("next_select()) - { - len+= lastop; - lastop= my_snprintf(table_name_buffer + len, NAME_LEN - len, - "%u,", sl->select_number); - } - if (sl || len + lastop >= NAME_LEN) - { - memcpy(table_name_buffer + len, STRING_WITH_LEN("...>") + 1); - len+= 4; - } - else - { - len+= lastop; - table_name_buffer[len - 1]= '>'; // change ',' to '>' - } - item_list.push_back(new Item_string(table_name_buffer, len, cs)); - } - /* partitions */ - if (join->thd->lex->describe & DESCRIBE_PARTITIONS) - item_list.push_back(item_null); - /* type */ - item_list.push_back(new Item_string(join_type_str[JT_ALL], - strlen(join_type_str[JT_ALL]), - cs)); - /* possible_keys */ - item_list.push_back(item_null); - /* key*/ - item_list.push_back(item_null); - /* key_len */ - item_list.push_back(item_null); - /* ref */ - item_list.push_back(item_null); - /* in_rows */ - if (join->thd->lex->describe & DESCRIBE_EXTENDED) - item_list.push_back(item_null); - /* rows */ - item_list.push_back(item_null); - /* extra */ - if (join->unit->global_parameters->order_list.first) - item_list.push_back(new Item_string("Using filesort", - 14, cs)); - else - item_list.push_back(new Item_string("", 0, cs)); - - if (result->send_data(item_list)) + if (print_fake_select_lex_join(result, on_the_fly, + join->select_lex, + join->thd->lex->describe)) error= 1; } else if (!join->select_lex->master_unit()->derived || diff --git a/sql/sql_select.h b/sql/sql_select.h index f329f51707f..d6379f3ea92 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -1465,6 +1465,9 @@ inline bool optimizer_flag(THD *thd, uint flag) return (thd->variables.optimizer_switch & flag); } +int print_fake_select_lex_join(select_result_sink *result, bool on_the_fly, + SELECT_LEX *select_lex, uint8 select_options); + /* Table elimination entry point function */ void eliminate_tables(JOIN *join);