This example demonstrates how to use the following new functions of the otl_connect class for OTL/OCI8:
#include <iostream.h> #include <stdio.h>
#define OTL_ORA8 // Compile OTL 4.0/OCI8
#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>=:f<int> and f1<=:f*2",
// SELECT statement
db // connect object
);
// create select stream
float f1;
char f2[31];
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 OCI environment
try{
db.rlogon("scott/tiger"); // connect to Oracle
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 number, f2 varchar2(30))"
); // create table
insert(); // insert records into table
db.logoff(); // disconnect from Oracle
db.server_attach(); // attach to the local Oracle server
// In order to connect to a remote server,
// a TNS alias needs to be specified
cout<<"Session begin ==> "<<1<<endl;
db.session_begin("scott","tiger");
// begin session; this function is much faster
// than rlogon() and should be used (see the Oracle
// manuals for more detail) in high-speed processing
// systems, possibly with thousands of users.
// this technique can be used instead of traditional
// connection pooling.
cout<<"Session end ==> "<<1<<endl;
db.session_end(); // end session
for(int i=2;i<=100;++i){
cout<<"Session begin ==> "<<i<<endl;
db.session_reopen();
// reopen session, previously opened by session_begin().
// this function open a new session with the same username/password,
// that were used by the previous session_begin() call. Session_reopen()
// works 5-10% faster than session_begin(), because the username and
// password attributes of the OCI8 connect structure have been already
// set.
select(); // select records from table
cout<<"Session end ==> "<<i<<endl;
db.session_end(); // end session
}
db.server_detach(); // detach from the Oracle server
}
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(); // make sure that the program gets disconnected from Oracle
return 0;
}
Repeated groups of the following lines:
Session begin ==> XXX f1=4, f2=Name4 f1=5, f2=Name5 f1=6, f2=Name6 f1=7, f2=Name7 f1=8, f2=Name8 Session end ==> XXX
Copyright © 1996, 2001, Sergei Kuchin, email: [email protected], [email protected] .
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.