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<TITLE>OTL 4.0, Example 76 (STL-compliant OTL stream iterators, Oracle 8)</TITLE>
<META NAME="Author" CONTENT="Sergei Kuchin">
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<H1 ALIGN=CENTER>OTL 4.0, Example 76 (STL-compliant OTL stream iterators,
Oracle 8)</H1>
<H1>Example 76 (STL-compliant OTL stream iterators, Oracle 8)</H1>
<P>This example demonstrates STL-compliant OTL stream itertors, std::strings,
and ANSI C++ typecasts. </P>
<H2>Source Code</H2>
<PRE>#include <iostream>
#include <vector>
#include <iterator>
#include <string></PRE>
<PRE>#define OTL_ORA8 // Compile OTL 4.0/OCI8
#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;
<A HREF="otl3_connect_class.htm">otl_connect</A> 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& row)
{
f1=row.f1;
f2=row.f2;
}
// assignment operator
row& operator=(const row& row)
{
f1=row.f1;
f2=row.f2;
return *this;
}
};
// redefined operator>> for reading row& from otl_stream
otl_stream& operator>>(otl_stream& s, row& row)
{
s>>row.f1>>row.f2;
return s;
}
// redefined operator<< for writing row& into otl_stream
otl_stream& operator<<(otl_stream& s, const row& row)
{
s<<row.f1<<row.f2;
return s;
}
// redefined operator<< writing row& into ostream
ostream& operator<<(ostream& s, const row& row)
{
s<<"f1="<<row.f1<<", f2="<<row.f2;
return s;
}
void insert()
// insert rows into table
{
<A HREF="otl3_stream_class.htm">otl_stream</A> 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(),
<A HREF="otl3_output_iterator.htm">otl_output_iterator</A><row>(o)
);
}
void select()
{
<A HREF="otl3_stream_class.htm">otl_stream</A> i(50, // buffer size
"select * from test_tab where f1>=:f<int> and f1<=:f*2",
// SELECT statement
db // connect object
);
// create select stream
vector<row> v; // vector of rows
// assigning :f = 8
i<<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(<A HREF="otl3_input_iterator.htm">otl_input_iterator</A><row,ptrdiff_t>(i),
<A HREF="otl3_input_iterator.htm">otl_input_iterator</A><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; // assigning :f = 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(<A HREF="otl3_input_iterator.htm">otl_input_iterator</A><row,ptrdiff_t>(i),
<A HREF="otl3_input_iterator.htm">otl_input_iterator</A><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()
{
<A HREF="otl3_connect_class.htm">otl_connect::otl_initialize</A>(); // initialize OCI environment
try{
db.rlogon("scott/tiger"); // connect to Oracle
<A HREF="otl3_const_sql.htm">otl_cursor::direct_exec
</A> (
db,
"drop table test_tab",
otl_exception::disabled // disable OTL exceptions
); // drop table
<A HREF="otl3_const_sql.htm">otl_cursor::direct_exec
</A> (
db,
"create table test_tab(f1 number, f2 varchar2(30))"
); // create table
insert(); // insert records into table
select(); // select records from table
}
catch(<A HREF="otl3_exception_class.htm">otl_exception</A>& 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 Oracle
return 0;
}
</PRE>
<H2>Output</H2>
<PRE>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
<HR WIDTH="100%"></PRE>
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<P>Copyright © 1996, 2008, Sergei Kuchin, email: <A HREF="mailto:skuchin@aceweb.com">skuchin@aceweb.com</A>,
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