ex167_oci8.cpp

一个跨平台的数据库操作库文件,可以轻松在linux和windows下进行数据库读写以及其他的操作,支持多种数据库,代码包含很多example,初学者很容易上手. OTL 是 Oracle, Odbc

#include <iostream>
using namespace std;
#include <stdio.h>

// Uncomment the line below when OCI7 is used with OTL
// #define OTL_ORA7 // Compile OTL 4.0/OCI7 

#define OTL_ORA8I // Compile OTL 4.0/OCI
// Uncomment the line below in case of Oracle 9i
//#define OTL_ORA9I 
#include <otlv4.h> // include the OTL 4.0 header file

otl_connect db; // connect object

void insert()
// insert rows into table
{ 
 otl_stream o(50, // buffer size
              "insert into test_tab values(:f1<float>,:f2<char[31]>)", 
                 // SQL statement
              db // connect object
             );
 char tmp[32];

 for(int i=1;i<=100;++i){
#if defined(_MSC_VER)
#if (_MSC_VER >= 1400) // VC++ 8.0 or higher
  sprintf_s(tmp,sizeof(tmp),"Name%d",i);
#else
  sprintf(tmp,"Name%d",i);
#endif
#else
  sprintf(tmp,"Name%d",i);
#endif
  o<<static_cast<float>(i)<<tmp;
 }
}

void select()
{ 
 otl_stream i(50, // buffer size
              "begin "
              "  open :cur for "
              "  select * " 
              "  from test_tab "
              "  where f1>=:f<char[40]> "
              "    and f1<=:f*2; "
              "end;", // Reference cursor SELECT statement
              db, // connect object
              ":cur" // reference cursor placeholder name
             ); 
   // create select stream
 
 float f1;
 char f2[31];
 
 try{
  cout<<"====> Starting a fetch sequence...."<<endl;
  i<<"xxx8"; // assigning :f = "xxx8", it's obviously 
             // invalid for a numeric column
    // SELECT automatically executes when all input variables are
    // assigned. First portion of output rows is fetched to the buffer

  while(!i.eof()){ // while not end-of-data
   i>>f1>>f2;
   cout<<"f1="<<f1<<", f2="<<f2<<endl;
  } 
 }catch(otl_exception& p){
  cerr<<"===> A database exception is caught: "<<endl;
  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
  cerr<<"===> Cleaning up the stream's error flags"<<endl;
  i.clean();
 }

 cout<<"====> Starting another fetch sequence..."<<endl;
 i<<"4"; // assigning :f = 4
   // SELECT automatically executes when all input variables are
   // assigned. First portion of output rows is fetched to the buffer

 while(!i.eof()){ // while not end-of-data
  i>>f1>>f2;
  cout<<"f1="<<f1<<", f2="<<f2<<endl;
 }

}

int main()
{
 otl_connect::otl_initialize(); // initialize the environment
 try{

  db.rlogon("scott/tiger"); // connect to the database

  otl_cursor::direct_exec
   (
    db,
    "drop table test_tab",
    otl_exception::disabled // disable OTL exceptions
   ); // drop table

  otl_cursor::direct_exec
   (
    db,
    "create table test_tab(f1 int, f2 varchar(30))"
    );  // 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

 return 0;

}