database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-30 16:24:05 +03:00
Code Activity

after review changes

Browse Source
This commit is contained in:
bell@sanja.is.com.ua
2004-05-19 17:07:28 +03:00
parent bb34b56bfd
commit d42d709171
6 changed files with 52 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
sql/sql_select.cc
View File

@ -9133,7 +9133,7 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
if (message)
{
item_list.push_back(new Item_int((longlong)
item_list.push_back(new Item_int((int32)
join->select_lex->select_number));
item_list.push_back(new Item_string(join->select_lex->type,
strlen(join->select_lex->type), cs));
@ -9146,23 +9146,44 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
else if (join->select_lex == join->unit->fake_select_lex)
{
/*
Here is guessing about fake_select_lex to avoid union SELECT
execution to get accurate information
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[64];
char table_name_buffer[NAME_LEN];
item_list.empty();
/* id */
item_list.push_back(new Item_int((int32)
join->select_lex->select_number));
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 */
int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1,
"<union%d>",
-join->select_lex->select_number);
item_list.push_back(new Item_string(table_name_buffer, len, cs));
{
SELECT_LEX *sl= join->unit->first_select();
uint len= 6, lastop= 0;
memcpy(table_name_buffer, "<union", 6);
for (; sl && len + lastop + 5 < NAME_LEN; sl= sl->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, "...>", 5);
len+= 4;
}
else
{
len+= lastop;
table_name_buffer[len - 1]= '>'; // change ',' to '>'
}
item_list.push_back(new Item_string(table_name_buffer, len, cs));
}
/* type */
item_list.push_back(new Item_string(join_type_str[JT_ALL],
strlen(join_type_str[JT_ALL]),
cs));
@ -9195,7 +9216,7 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
TABLE *table=tab->table;
char buff[512],*buff_ptr=buff;
char buff1[512], buff2[512];
char table_name_buffer[64];
char table_name_buffer[NAME_LEN];
String tmp1(buff1,sizeof(buff1),cs);
String tmp2(buff2,sizeof(buff2),cs);
tmp1.length(0);
@ -9203,7 +9224,7 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
item_list.empty();
/* id */
item_list.push_back(new Item_int((int32)
item_list.push_back(new Item_uint((uint32)
join->select_lex->select_number));
/* select_type */
item_list.push_back(new Item_string(join->select_lex->type,
@ -9379,7 +9400,7 @@ int mysql_explain_union(THD *thd, SELECT_LEX_UNIT *unit, select_result *result)
}
if (first->next_select())
{
unit->fake_select_lex->select_number= -first->select_number;
unit->fake_select_lex->select_number= UINT_MAX; // jost for initialization
unit->fake_select_lex->type= "UNION RESULT";
unit->fake_select_lex->options|= SELECT_DESCRIBE;
if (!(res= unit->prepare(thd, result, SELECT_NO_UNLOCK | SELECT_DESCRIBE)))