原创内容，转载请注明原文网址：http://homeqin.cn/a/wenzhangboke/jishutiandi/2019/1019/683.html
1、MySQL安置及简略设置
(1)安置：在OSX体系下，能够应用万能的“brew install”号令来举行常州微信公众平台安置：brew isntall mysql(默认安置非常新版的MySQL)
(2)启动：brew services start mysql
(3)点窜密码：update user set authentication_string = password('password'), password_expired = 'N', password_last_changed = now() where user = 'root';
-->flush privileges;(让点窜后的密码见效)
(4)容许远程走访：update mysql.user set host = '%' where user = 'root';
2、MySQL Connector/C++安置
(1)下载：MySQL Connector/C++源码能够从这里下载
(2)安置：解压后将“include”目录下的文件复制到“/usr/local/include”目录下，“lib”目录下的文件复制到“/usr/local/lib”目录下即可
3、示例代码（基于单例模式的懒汉模子）
CConnPool.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
/*
* CConnPool.h
*
* Created on: Mar 15, 2018
* Author: root
*/
#ifndef SRC_CCONNPOOL_H_
#define SRC_CCONNPOOL_H_
#include <list>
#include <string>
#include <pthread.h>
#include <mysql_connection.h>
#include <mysql_driver.h>
#include <cppconn/exception.h>
#include <cppconn/driver.h>
#include <cppconn/connection.h>
#include <cppconn/resultset.h>
#include <cppconn/prepared_statement.h>
#include <cppconn/statement.h>
using namespace sql;
using namespace std;
class CConnPool {
public:
~CConnPool();
void InitConnpool(string url, string user, string password, int maxSize);
Connection* GetConnection();
void ReleaseConnection(Connection* conn);
static CConnPool *GetInstance();
private:
CConnPool();
Connection*CreateConnection(); //创建一个持续
void InitConnection(int iInitialSize); //初始化数据库持续池
void DestoryConnection(Connection *conn); //烧毁数据库持续工具
void DestoryConnPool(); //烧毁数据库持续池
CConnPool(string url, string user, string password, int maxSize); //组织方法
private:
int curSize; //目前已确立的数据库持续数目
int maxSize; //持续池中定义的非常大数据库持续数
string user;
string password;
string url;
list<Connection*> connList; //持续池的容器部队 STL list 双向链表
pthread_mutex_t lock; //线程锁
static CConnPool *connPool;
Driver*driver;
};
#endif /* SRC_CCONNPOOL_H_ */
CConnPool.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
/*
* CConnPool.cpp
*
* Created on: Mar 15, 2018
* Author: root
*/
#include <stdexcept>
#include <exception>
#include <cstdio>
#include "CConnPool.h"
CConnPool *CConnPool::connPool = NULL;
//CConnPool* CConnPool::connPool = new CConnPool();
CConnPool::CConnPool()
{
// TODO Auto-generated constructor stub
}
void CConnPool::InitConnpool(string url, string user, string password,
int maxSize)
{
this->maxSize = maxSize;
this->curSize = 0;
this->user = user;
this->password = password;
this->url = url;
try
{
this->driver = sql::mysql::get_driver_instance();
}
catch (sql::SQLException &e)
{
perror("驱动持续失足;\r");
}
catch (std::runtime_error &e)
{
perror("常州微信小程序开发运行失足了\r");
}
this->InitConnection(maxSize / 2);
pthread_mutex_init(&lock, NULL);
}
CConnPool::CConnPool(string url, string user, string password, int maxSize)
{
this->maxSize = maxSize;
this->curSize = 0;
this->user = user;
this->password = password;
this->url = url;
try
{
this->driver = sql::mysql::get_driver_instance();
}
catch (sql::SQLException &e)
{
perror("驱动持续失足;\r");
}
catch (std::runtime_error &e)
{
perror("运行失足了\r");
}
this->InitConnection(maxSize / 2);
pthread_mutex_init(&lock, NULL);
}
CConnPool *CConnPool::GetInstance()
{
if (connPool == NULL)
connPool = new CConnPool("tcp://127.0.0.1:3306", "root", "123456",
10);
return connPool;
}
void CConnPool::InitConnection(int num)
{
Connection *conn;
pthread_mutex_lock(&lock);
for (int i = 0; i < num; ++i)
{
conn = CreateConnection();
if (conn)
{
connList.push_back(conn);
++curSize;
}
else
{
perror("创建CONNECTION失足");
}
}
pthread_mutex_unlock(&lock);
}
Connection *CConnPool::CreateConnection()
{
Connection *conn;
try
{
conn = driver->connect(url, user, password); //确立持续
return conn;
}
catch (sql::SQLException &e)
{
perror(e.what());
return NULL;
}
catch (std::runtime_error &e)
{
perror(e.what());
return NULL;
}
}
Connection *CConnPool::GetConnection()
{
Connection *conn;
pthread_mutex_lock(&lock);
if (connList.size() > 0)
{
conn = connList.front();
connList.pop_front();
if (conn->isClosed())
{
delete conn;
conn = CreateConnection();
}
if (conn == NULL)
--curSize;
pthread_mutex_unlock(&lock);
return conn;
}
else
{
if (curSize < maxSize)
{
conn = CreateConnection();
if (conn)
{
++curSize;
pthread_mutex_unlock(&lock);
return conn;
}
else
{
pthread_mutex_unlock(&lock);
return NULL;
}
}
else
{
pthread_mutex_unlock(&lock);
return NULL;
}
}
}
void CConnPool::ReleaseConnection(Connection *conn)
{
if (conn)
{
pthread_mutex_lock(&lock);
connList.push_back(conn);
pthread_mutex_unlock(&lock);
}
}
CConnPool::~CConnPool()
{
this->DestoryConnPool();
}
void CConnPool::DestoryConnPool()
{
list<Connection *>::iterator iter;
pthread_mutex_lock(&lock);
for (iter = connList.begin(); iter != connList.end(); ++iter)
this->DestoryConnection(*iter);
curSize = 0;
connList.clear();
pthread_mutex_unlock(&lock);
}
void CConnPool::DestoryConnection(Connection *conn)
{
if (conn)
{
try
{
conn->close();
}
catch (sql::SQLException &e)
{
perror(e.what());
}
catch (std::exception &e)
{
perror(e.what());
}
delete conn;
}
}
main.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
#include <iostream>
#include <string>
#include "CConnPool.h"
using std::cout;
using std::endl;
using std::string;
CConnPool *connpool = CConnPool::GetInstance();
int main(int argc, char *argv[])
{
Connection *conn;
Statement *state;
ResultSet *result;
conn = connpool->GetConnection();
state = conn->createStatement();
state->execute("use mysql");
result = state->executeQuery("select host,user from user");
while (result->next())
{
try
{
string user = result->getString("user");
string host = result->getString("host");
cout << user << "@" << host << endl;
}
catch (sql::SQLException &e)
{
cout << e.what() << endl;
}
}
delete result;
delete state;
connpool->ReleaseConnection(conn);
getchar();
return 0;
}
分类: C/C++
上篇：上一篇：win10 CompatTelRunner或task scheduler占用CPU过高
下篇：下一篇：Qt5_vs2013_error_C2001: 常量中有换行符
