Linux下用OTL操作MySql（包含自己封装的类库及演示样例代码下载）
首先重点推荐介绍otl介绍及使用方法的文章：http://blog.csdn.net/rain_qingtian/article/details/12749177
（1）首先安装MySql数据库服务：
下载：http://pan.baidu.com/s/1i3rCnQH
安装步骤：http://write.blog.csdn.net/postedit/23966241
（2）安装navicat数据库client：
下载：http://pan.baidu.com/s/1i3kMOy5
安装步骤：傻瓜安装，选择字符集的时候自己依据情况选择gbk2312,或者utf-8（一般涉及到网络传输或者跨平台，比方和java项目公用数据。会选择utf-8）
（3）安装odbc数据库连接驱动：
下载：http://pan.baidu.com/s/1sjPicjF
安装：http://jingyan.baidu.com/article/8065f87f38b31423312498e4.html 注意这里的安装介绍里面的：打开数据源：開始->设置->控制面板->“管理工具”找到“数据源”
（4）使用otl操作mysql
（4.1）最新封装C++操作otl类库及演示样例代码下载（可直接执行）：http://pan.baidu.com/s/1i31bZUX
（4.2）以下的演示样例更加简单，因为没有封装otl，仅仅是使用了全局的otl_connect来实现的，方便入门
创建VS项目：
包括头文件：otl4.h
下载：http://pan.baidu.com/s/1c0tK1jE
包括源文件：
#include <iostream>
using namespace std;
#include <stdio.h>
#define OTL_ODBC // CompileOTL 4.0/ODBC
// Thefollowing #define is required with MyODBC 5.1 and higher
#define OTL_ODBC_SELECT_STM_EXECUTE_BEFORE_DESCRIBE
#define OTL_UNICODE // CompileOTL with Unicode
#include "otlv4.h"// include the OTL 4.0 header file
otl_connect db; // connect object
void insert()
// insert rowsinto table
{
otl_stream o(1, //buffer size should be == 1 always on INSERT.
"insert into test_tab values(:f1<int>,:f2<char[5]>)",
// SQLstatement, char[5] means 5 2-byte
// Unicodecharatcters including a null
// terminator
db // connectobject
);
unsigned short tmp[32]; // Nullterminated Unicode character array.
for(int i=1;i<=100;++i){
o<<i;
tmp[0]=1111; //Unicode character (decimal code of 1111)
tmp[1]=2222; //Unicode character (decimal code of 2222)
tmp[2]=3333; //Unicode chracater (decimal code of 3333)
tmp[3]=4444; //Unicode chracater (decimal code of 4444)
tmp[4]=0; //Unicode null terminator
o<<(unsigned char*)tmp;
// overloadedoperator<<(const unsigned char*) in the case of Unicode
// OTL acceptsa pointer to a Unicode character array.
//operator<<(const unsigned short*) wasn't overloaded
// in order toavoid ambiguity in C++ type casting.
}
}
void select()
{
otl_stream i(50, //buffer size
" select* from test_tab "
"where f1>= :f11<int> "
" and f1 <= :f12<int>*2 ",
// SELECTstatement
db // connectobject
);
// create selectstream
int f1;
unsigned short f2[32];
i<<8<<8; // assigning :f11 = 8, f12 = 8
// SELECTautomatically executes when all input variables are
// assigned. Firstportion of output rows is fetched to the buffer
while(!i.eof()){// while not end-of-data
i>>f1;
i>>(unsigned char*)f2;
// overloaded operator>>(unsignedchar*) in the case of Unicode
// OTL acceptsa pointer to a Unicode chracter array.
//operator>>(unsigned short*) wasn't overloaded
// in order toavoid ambiguity in C++ type casting.
cout<<"f1="<<f1<<", f2=";
for(int j=0;f2[j]!=0;++j)
cout<<""<<f2[j];
cout<<endl;
}
i<<4<<4; // assigning :f11 = 4, :f12 = 4
// SELECTautomatically executes when all input variables are
// assigned. Firstportion of output rows is fetched to the buffer
while(!i.eof()){// while not end-of-data
i>>f1>>(unsigned char*)f2;
cout<<"f1="<<f1<<", f2=";
for(int j=0;f2[j]!=0;++j)
cout<<""<<f2[j];
cout<<endl;
}
}
int main()
{
otl_connect::otl_initialize(); // initialize the database API environment
try{
// connect to the database user/psw/dsn,这里的dsn是odbc创建数据源的时候设置的，
//注意dsn是odbc连接的名字。不是数据库的名字。otl是通过odbc的名字找到数据库的，
//而这个名字对于的配置里面
//已经包括了IP,端口等信息，仅仅要你提供username和password就能够訪问了
//见http://jingyan.baidu.com/article/8065f87f38b31423312498e4.html
db.rlogon("root/123456@local_connect");
otl_cursor::direct_exec
(
db,
"drop table test_tab",
otl_exception::disabled // disable OTL exceptions
); // droptable
otl_cursor::direct_exec
(
db,
"create table test_tab(f1 int, f2 varchar(11))"
); // create table
insert(); //insert records into table
select(); //select records from table
}
catch(otl_exception&p){ // intercept OTL exceptions
cerr<<p.msg<<endl; // print out error message
cerr<<p.stm_text<<endl; // print out SQL that caused the error
cerr<<p.var_info<<endl; // print out the variable that caused the error
}
db.logoff(); //disconnect from the database
getchar();
return 0;
}输出：
f1=8, f2=1111222233334444
f1=9, f2=1111222233334444
f1=10, f2=1111222233334444
f1=11, f2=1111222233334444
f1=12, f2=1111222233334444
f1=13, f2=1111222233334444
f1=14, f2=1111222233334444
f1=15, f2=1111222233334444
f1=16, f2=1111222233334444
f1=4, f2=1111222233334444
f1=5, f2=1111222233334444
f1=6, f2=1111222233334444
f1=7, f2=1111222233334444
f1=8, f2=1111222233334444
较好的介绍样例地址：http://www.cnblogs.com/skyme/archive/2010/11/08/1871509.html
语法总结：
连接初始化：otl_connect::otl_initialize();
连接对象：otl_connect db; // connect object
连接数据库： db.rlogon("UID=scott;PWD=tiger;DSN=postgresql"); // connect to ODBC
连接数据库一般放在try子句中：
try{
db.rlogon("UID=scott;PWD=tiger;DSN=postgresql"); // connect to ODBC
}
catch(otl_exception& p){ // intercept OTL exceptions
cerr<<p.msg<<endl; // print out error message
cerr<<p.stm_text<<endl; // print out SQL that caused the error
cerr<<p.sqlstate<<endl; // print out SQLSTATE message
cerr<<p.var_info<<endl; // print out the variable that caused the error
}
db.logoff(); // disconnect from ODBC
数据库操作：在数据库的连接和断开之间执行，往往同一个连接内部进行多个数据库操作
db.rlogon("UID=scott;PWD=tiger;DSN=postgresql"); // connect to ODBC
otl_cursor::direct_exec(
db,
"drop table test_tab",
otl_exception::disabled // disable OTL exceptions
); // droptable
表的创建
string sql ="create table test_tab(f1 int, f2 varchar(11))";
//create table person_tab(age int, student_name char(30))
otl_cursor::direct_exec
(
db,
sql.c_str();
); // create table
表的删除
otl_cursor::direct_exec
(
db,
"drop table test_tab",
otl_exception::disabled // disable OTL exceptions
); // droptable
插入
otl_stream o(50, // buffer size
"insert into test_tab "
"values(:f1<int>,:f2<char[31]>,:f3<timestamp>)",
// SQL statement
db // connect object
);
////
o<<i<<f2<<f3;
查询
otl_stream i(50, // buffer size
"select * from test_tab where f1>=:f11<int> and f1<=:f12<int>*2",
// SELECT statement
db // connect object
);
