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主要用于维护C结构的查询和返回。
#include <mysql/mysql.h>
typedef std::string string;
struct mysql_parm{
string host;
string user;
string password;
string database;
string unixsock;
};
class DBSTMT;
class DBMysql;
class DBSTMT{
DBSTMT(const DBSTMT&);
DBSTMT& operator=(const DBSTMT&);
MYSQL_STMT* stmt_;
public:
DBSTMT(pcsz_t query,DBMysql& mysql);
void execute(){
if(mysql_stmt_execute(stmt_))
throw mysql_stmt_error(stmt_);
}
void execute(MYSQL_BIND* bind){
if(mysql_stmt_execute(stmt_))
throw mysql_stmt_error(stmt_);
if(mysql_stmt_bind_result(stmt_,bind)){
throw mysql_stmt_error(stmt_);
}
if(mysql_stmt_store_result(stmt_))
throw mysql_stmt_error(stmt_);
}
//void execute(){
// if(mysql_stmt_execute(stmt_))
// throw mysql_stmt_error(stmt_);
//}
void bind(MYSQL_BIND* bind){
if(mysql_stmt_bind_param(stmt_,bind) )
throw mysql_stmt_error(stmt_);
}
int fetch(){
return mysql_stmt_fetch(stmt_)==0;
}
~DBSTMT(){
if(stmt_){
mysql_stmt_close(stmt_);
}
}
};
class DBMysql{
DBMysql(const DBMysql&);
DBMysql&operator=(const DBMysql&);
MYSQL * mysqlPtr_;
uint32_t errno_;
protected:
friend class DBSTMT;
MYSQL_STMT* _createSTMT(){
MYSQL_STMT *ret=mysql_stmt_init(mysqlPtr_);
if(ret)
return ret;
errno_=mysql_errno(mysqlPtr_);
throw mysql_error(mysqlPtr_);
}
public:
const char* strerr(){
return mysql_error(mysqlPtr_);
}
DBMysql():mysqlPtr_(NULL){
mysqlPtr_=mysql_init(NULL);
if(NULL== mysqlPtr_)
throw "Mysql :outof memory";
}
void open(const mysql_parm& parm){
if(!mysql_real_connect(mysqlPtr_,
parm.host.c_str(),
parm.user.c_str(),
parm.password.c_str(),
parm.database.c_str(),
0,
parm.unixsock.c_str(),
0 ))
{
errno_=mysql_errno(mysqlPtr_);
throw(mysql_error(mysqlPtr_));
}
}
void close(){
if(mysqlPtr_)
{
mysql_close(mysqlPtr_);
mysqlPtr_=NULL;
}
}
};
DBSTMT::DBSTMT(pcsz_t query,DBMysql& mysql):stmt_(NULL){
stmt_=mysql._createSTMT();
if(!stmt_)
throw mysql.strerr();
if( mysql_stmt_prepare(stmt_,query,strlen(query)) )
{
//const char* err=
throw mysql_stmt_error(stmt_);
}
}
#define DECL_BIND(h,n)\
class bind_##h:public h{\
typedef h parent;\
MYSQL_BIND _bind[n];\
my_bool _is_null[n];\
unsigned long _length[n];\
public:\
bind_##h(){\
int i=0;\
bzero(_bind,sizeof(_bind));
#define BIND_BIN(x,l)\
_bind[i].buffer_type= MYSQL_TYPE_STRING;\
_bind[i].buffer= (char *)&(parent::x);\
_bind[i].buffer_length= l;\
_bind[i].is_null= _is_null+i;\
_bind[i].length= _length+i;\
++i;
#define BIND_INT(x)\
_bind[i].buffer_type= MYSQL_TYPE_LONG;\
_bind[i].buffer= (char *)&(parent::x);\
_bind[i].buffer_length= 0;\
_bind[i].is_null= _is_null+i;\
_bind[i].length= _length+i;\
++i;
#define END_BIND(h) }\
operator MYSQL_BIND*(){\
return _bind;\
}\
};
使用方法;
例如想查询的内容具有以下结构
struct account{
char user[36];
byte password[16];
uint32_t status;
uint32_t id;
};
//声明查询bind 结构account,参数4个
DECL_BIND(account,4)
BIND_BIN(user,32)
BIND_BIN(password,16)
BIND_INT(status)
BIND_INT(id)
END_BIND(account)
int main(){
try{
DBMysql mysql;
mysql_parm parm;
parm.host="localhost";
parm.user="root";
parm.password="test";
parm.unixsock="/var/lib/mysql/mysql.sock";
parm.database="testdb";
mysql.open(parm);//打开数据库
DBSTMT smt("select user,password,status,id from account",mysql);//生成一个查询语法
DBSTMT smt1("insert into account(user,password,status) value(?,?,?)",mysql);//另外一个
//
bind_account acc;
smt.execute(acc);//执行查询，并bind返回结果到account结构
while(smt.fetch()){
printf("%s %d %d\n",acc.user,acc.status,acc.id);
};
smt1.bind(acc);//bind查询参数
smt1.execute();//执行
}catch(const char* err){
printf("error:%s\n",err);
}
}
[[i] 本帖最后由 yejr 于 2006-3-21 14:10 编辑 [/i]] |
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发表于 2006-03-21 13:55
发表于 2006-03-21 14:09
