This example demonstrates STL-compliant OTL/ODBC stream itertors, std::strings, and ANSI C++ typecasts.
#include <iostream>
#include <vector>
#include <iterator>
#include <string>
#define OTL_ODBC_UNIX // Compile OTL 4.0/ODBC
#define OTL_STL // Turn on STL features
#define OTL_ANSI_CPP // Turn on ANSI C++ typecasts
#include <otlv4.h> // include the OTL 4.0 header file
using namespace std;
otl_connect db; // connect object
// row container class
class row{
public:
int f1;
string f2;
// default constructor
row(){f1=0;}
// destructor
~row(){}
// copy constructor
row(const row& arow)
{
f1=arow.f1;
f2=arow.f2;
}
// assignment operator
row& operator=(const row& arow)
{
f1=arow.f1;
f2=arow.f2;
return *this;
}
};
// redefined operator>> for reading row& from otl_stream
otl_stream& operator>>(otl_stream& s, row& arow)
{
s>>arow.f1>>arow.f2;
return s;
}
// redefined operator<< for writing row& into otl_stream
otl_stream& operator<<(otl_stream& s, const row& arow)
{
s<<arow.f1<<arow.f2;
return s;
}
// redefined operator<< writing row& into ostream
ostream& operator<<(ostream& s, const row& arow)
{
s<<"f1="<<arow.f1<<", f2="<<arow.f2;
return s;
}
void insert()
// insert rows into table
{
otl_stream o(50, // buffer size
"insert into test_tab values(:f1<int>,:f2<char[31]>)",
// SQL statement
db // connect object
);
row r; // single row buffer
vector<row> vo; // vector of rows
// populate the vector
for(int i=1;i<=100;++i){
r.f1=i;
r.f2="NameXXX";
vo.push_back(r);
}
cout<<"vo.size="<<vo.size()<<endl;
// insert vector into table
copy(vo.begin(),
vo.end(),
otl_output_iterator<row>(o)
);
}
void select()
{
otl_stream i(50, // buffer size
"select * from test_tab where f1>=:f1<int> and f1<=:f11<int>*2",
// SELECT statement
db // connect object
);
// create select stream
vector<row> v; // vector of rows
// assigning :f1 = 8, :f11 = 8
i<<8<<8;
// SELECT automatically executes when all input variables are
// assigned. First portion of out rows is fetched to the buffer
// copy all rows to be fetched into the vector
copy(otl_input_iterator<row,ptrdiff_t>(i),
otl_input_iterator<row,ptrdiff_t>(),
back_inserter(v));
cout<<"Size="<<v.size()<<endl;
// send the vector to cout
copy(v.begin(), v.end(), ostream_iterator<row>(cout, "\n"));
// clean up the vector
v.erase(v.begin(),v.end());
i<<4<<4; // assigning :f1 = 4, :f11 = 4
// SELECT automatically executes when all input variables are
// assigned. First portion of out rows is fetched to the buffer
// copy all rows to be fetched to the vector
copy(otl_input_iterator<row,ptrdiff_t>(i),
otl_input_iterator<row,ptrdiff_t>(),
back_inserter(v));
cout<<"Size="<<v.size()<<endl;
// send the vector to cout
copy(v.begin(), v.end(), ostream_iterator<row>(cout, "\n"));
}
int main()
{
otl_connect::otl_initialize(); // initialize ODBC environment
try{
db.rlogon("scott/tigger@sybsql"); // connect to ODBC
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 ODBC
return 0;
}
vo.size=100
Size=9
f1=8, f2=NameXXX
f1=9, f2=NameXXX
f1=10, f2=NameXXX
f1=11, f2=NameXXX
f1=12, f2=NameXXX
f1=13, f2=NameXXX
f1=14, f2=NameXXX
f1=15, f2=NameXXX
f1=16, f2=NameXXX
Size=5
f1=4, f2=NameXXX
f1=5, f2=NameXXX
f1=6, f2=NameXXX
f1=7, f2=NameXXX
f1=8, f2=NameXXX
Copyright © 1996-2024, Sergei Kuchin, email: skuchin@gmail.com, skuchin@gmail.com.
Permission to use, copy, modify and redistribute this document for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies. THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.