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void dGet_value2(void* *p2)
{
  printf("&p2:0x%04x\n", &p2);
  printf("p2:0x%04x\n", p2);
  printf("*p2:0x%04x\n", *p2);
  printf("\n");

  static int value = 5;
  *p2 = &value;
}

void dGet_value1(int* *p1)
{
  printf("&p1:0x%04x\n", &p1);
  printf("p1:0x%04x\n", p1);
  printf("*p1:0x%04x\n", *p1);
  printf("\n");

  dGet_value2((void **)&(*p1));
}
int _tmain(int argc, _TCHAR* argv[])
{
  int* pmain;
  printf("&pmain:0x%04x\n", &pmain);
  printf("pmain:0x%04x\n", pmain);
  printf("\n");

  dGet_value1(&pmain);

  printf("pmain-> %d\n",*pmain);
	return 0;
}

하나씩 설치하다가 잘안되서...
깔끔하게 APM_Setup 으로 설치하였다 ~! (XP환경)

[InnoDB]

1. InnoDB가 사용가능한지 확인해본다.

mysql> show variables like 'have_innodb';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| have_innodb   | YES   |
+---------------+-------+
1 row in set (0.00 sec)

!!! 여기서 Value에 Disable라고 뜬다면, my.ini를 열어서...
# BDB타입을 사용할지 하지 않을지
#skip-bdb <- 이부분 앞에 #으로 바꿔주고 mysql 재시작 하면 된다 ~

2. 설정 상태 확인한다.
mysql> show status like '%innodb%';
+-----------------------------------+---------+
| Variable_name                     | Value   |
+-----------------------------------+---------+
| Com_show_innodb_status            | 0       |
| Innodb_buffer_pool_pages_data     | 19      |
| Innodb_buffer_pool_pages_dirty    | 0       |
| Innodb_buffer_pool_pages_flushed  | 0       |
| Innodb_buffer_pool_pages_free     | 493     |
| Innodb_buffer_pool_pages_misc     | 0       |
| Innodb_buffer_pool_pages_total    | 512     |
| Innodb_buffer_pool_read_ahead_rnd | 1       |
| Innodb_buffer_pool_read_ahead_seq | 0       |
| Innodb_buffer_pool_read_requests  | 77      |
| Innodb_buffer_pool_reads          | 12      |
| Innodb_buffer_pool_wait_free      | 0       |
| Innodb_buffer_pool_write_requests | 0       |
| Innodb_data_fsyncs                | 3       |
| Innodb_data_pending_fsyncs        | 0       |
| Innodb_data_pending_reads         | 0       |
| Innodb_data_pending_writes        | 0       |
| Innodb_data_read                  | 2494464 |
| Innodb_data_reads                 | 29      |
| Innodb_data_writes                | 3       |
| Innodb_data_written               | 1536    |
| Innodb_dblwr_pages_written        | 0       |
| Innodb_dblwr_writes               | 0       |
| Innodb_log_waits                  | 0       |
| Innodb_log_write_requests         | 0       |
| Innodb_log_writes                 | 1       |
| Innodb_os_log_fsyncs              | 3       |
| Innodb_os_log_pending_fsyncs      | 0       |
| Innodb_os_log_pending_writes      | 0       |
| Innodb_os_log_written             | 512     |
| Innodb_page_size                  | 16384   |
| Innodb_pages_created              | 0       |
| Innodb_pages_read                 | 19      |
| Innodb_pages_written              | 0       |
| Innodb_row_lock_current_waits     | 0       |
| Innodb_row_lock_time              | 0       |
| Innodb_row_lock_time_avg          | 0       |
| Innodb_row_lock_time_max          | 0       |
| Innodb_row_lock_waits             | 0       |
| Innodb_rows_deleted               | 0       |
| Innodb_rows_inserted              | 0       |
| Innodb_rows_read                  | 0       |
| Innodb_rows_updated               | 0       |
+-----------------------------------+---------+
43 rows in set (0.00 sec)

Value에 설정된 값은 아마 my-innodb-heavy-4G.ini 를 편집하면 바뀔것 같다.
지금은 그냥 해보는게 중요해서..ㅎㅎ 건너뜀 ~ㅎ


3. 기존의 테이블 엔진 바꾸기
먼저 테이블 속성을 보자 ~

mysql> use testdb;
mysql> show table status where name='inno_test';
+-----------+--------+---------+------------+------+----------------+-----------
--+-------------------+--------------+-----------+----------------+-------------
--------+---------------------+------------+-----------------+----------+-------
---------+---------+
| Name      | Engine | Version | Row_format | Rows | Avg_row_length | Data_lengt
h | Max_data_length   | Index_length | Data_free | Auto_increment | Create_time
        | Update_time         | Check_time | Collation       | Checksum | Create
_options | Comment |
+-----------+--------+---------+------------+------+----------------+-----------
--+-------------------+--------------+-----------+----------------+-------------
--------+---------------------+------------+-----------------+----------+-------
---------+---------+
| inno_test | MyISAM |      10 | Fixed      |    1 |             65 |          6
5 | 18295873486192639 |         2048 |         0 |           NULL | 2009-11-20 1
5:20:35 | 2009-11-20 15:24:25 | NULL       | utf8_general_ci |     NULL |
         |         |
+-----------+--------+---------+------------+------+----------------+-----------
--+-------------------+--------------+-----------+----------------+-------------
--------+---------------------+------------+-----------------+----------+-------
---------+---------+
1 row in set (0.00 sec)

MyISAM 엔진이다. 이제 InnoDB로 변경 !!!

mysql> alter table inno_test type=innodb;
Query OK, 1 row affected, 1 warning (0.11 sec)
레코드: 1개  중복: 0개  경고: 0개

mysql> show table status where name='inno_test';
+-----------+--------+---------+------------+------+----------------+-----------
--+-----------------+--------------+-----------+----------------+---------------
------+-------------+------------+-----------------+----------+----------------+
----------------------+
| Name      | Engine | Version | Row_format | Rows | Avg_row_length | Data_lengt
h | Max_data_length | Index_length | Data_free | Auto_increment | Create_time
      | Update_time | Check_time | Collation       | Checksum | Create_options |
 Comment              |
+-----------+--------+---------+------------+------+----------------+-----------
--+-----------------+--------------+-----------+----------------+---------------
------+-------------+------------+-----------------+----------+----------------+
----------------------+
| inno_test | InnoDB |      10 | Compact    |    1 |          16384 |       1638
4 |               0 |        16384 |         0 |           NULL | 2009-11-20 15:
20:35 | NULL        | NULL       | utf8_general_ci |     NULL |                |
 InnoDB free: 4096 kB |
+-----------+--------+---------+------------+------+----------------+-----------
--+-----------------+--------------+-----------+----------------+---------------
------+-------------+------------+-----------------+----------+----------------+
----------------------+
1 row in set (0.00 sec)

InnoDB로 변경이 되었다 ~

4. 트랜잭션. rollback, commit 해보기

mysql> select * from inno_test;
+------+------+
| a    | b    |
+------+------+
|    2 | cho  |
+------+------+
1 row in set (0.00 sec)

mysql> begin;
Query OK, 0 rows affected (0.00 sec)

mysql> update inno_test set a=3;
Query OK, 1 row affected (0.00 sec)
일치하는 Rows : 1개 변경됨: 1개  경고: 0개

mysql> select * from inno_test;
+------+------+
| a    | b    |
+------+------+
|    3 | cho  |
+------+------+
1 row in set (0.00 sec)

mysql> rollback;
Query OK, 0 rows affected (0.03 sec)

mysql> select * from inno_test;
+------+------+
| a    | b    |
+------+------+
|    2 | cho  |
+------+------+
1 row in set (0.00 sec)

업데이트 쿼리를 하기전에 begin;을 입력하고 쿼리를 수행하면,
실제 데이터가 바로 바뀌지 않는다.
commit; 이 들어오면 실제로 바뀌게 되고 rollback;이 들어오면 적용하지 않게 된다.
이제는 commit;을 해보자.

mysql> begin;
Query OK, 0 rows affected (0.00 sec)

mysql> update inno_test set a=3;
Query OK, 1 row affected (0.00 sec)
일치하는 Rows : 1개 변경됨: 1개  경고: 0개

mysql> select * from inno_test;
+------+------+
| a    | b    |
+------+------+
|    3 | cho  |
+------+------+
1 row in set (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.03 sec)

mysql> select * from inno_test;
+------+------+
| a    | b    |
+------+------+
|    3 | cho  |
+------+------+
1 row in set (0.00 sec)

적용이 되었다 ~
트랜잭션에 대해서 좀 더 공부해야겠다 ~~~!

#include 
#include 
using namespace std;
int main()
{
int result, sum = 10, divisor=0;
result = sum / divisor;
cout << "Result = " << result << endl;
return 0;
}

#include 
#include 
using namespace std;
int main()
{
int result, sum = 10, divisor=0;
assert(divisor!=0);
result = sum / divisor;
cout << "Result = " << result << endl;
return 0;
}