#include <iostream>
using namespace std;
#include <stdio.h>
const int BASE_EXCEPTION=1; // "Base exception" class Id.
const int DB_BASE_EXCEPTION=2; // "DB Base exception" class Id.
// Let's assume that the following class is the base of
// the system exception class hierarchy
class my_base_exception{
public:
my_base_exception(){}
virtual ~my_base_exception(){}
virtual int getType(void) const
{
return BASE_EXCEPTION;
}
virtual int getErrorCode(void) const
{
return 0;
}
virtual const unsigned char* getErrorMessage(void) const
{
return 0;
}
};
#define OTL_ODBC_MSSQL_2005 // Compile OTL 4/ODBC, MS SQL 2005
#define OTL_FREETDS_ODBC_WORKAROUNDS // Enable the FreeTDS / ODBC workarounds for MS SQL
//#define OTL_ODBC // Compile OTL 4/ODBC. Uncomment this when used with MS SQL 7.0/ 2000
//#define OTL_ODBC_UNIX // Compile OTL 4 / ODBC. Uncomment this when used in Linux / Unix
// This #define connects the otl_exception class to the exception
// class hierarchy.
#define OTL_EXCEPTION_DERIVED_FROM my_base_exception
// This #define defines a set of new members in the otl_exception
// class
#define OTL_EXCEPTION_HAS_MEMBERS \
virtual int getType(void) const \
{ \
return DB_BASE_EXCEPTION; \
} \
\
virtual int getErrorCode(void) const \
{ \
return code; \
} \
\
virtual const unsigned char* getErrorMessage(void) const \
{ \
return msg; \
}
#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){
sprintf(tmp,"Name%d",i);
o<<(float)i<<tmp;
}
}
void select()
{
otl_stream i(50, // buffer size
"select * from test_tab where f1>=:f11<int> and f1<=:f12<int>*2",
// SELECT statement
db // connect object
);
// create select stream
float f1;
char f2[31];
i<<8<<8; // assigning :f12 = 8, :f12 = 8
// 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>>f2>>f1; // a typo: f2 instead of f1
cout<<"f1="<<f1<<", f2="<<f2<<endl;
}
i<<4<<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 ODBC environment
try{
db.rlogon("scott/tiger@freetds_mssql"); // connect to MS SQL Server
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(my_base_exception& ex){ // intercept the base exception
if(ex.getType()==DB_BASE_EXCEPTION){
// "database exception" is recognized
// here, the otl_exception can be analyzed, or simply printed out
cerr<<"Database exception:"<<endl;
cerr<<"Code: "<<ex.getErrorCode()<<endl; // print out error code
cerr<<"Message: "<<ex.getErrorMessage()<<endl; // print out the error message
}else{
// otherwise, do something else
cerr<<"Base exception was caught..."<<endl;
}
}
db.logoff(); // disconnect from MS SQL Server
return 0;
}
Database exception:
Code: 32000
Message: Incompatible data types in stream operation
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