This example demonstrates the otl_stream::describe_select() with a simple SELECT statement.
#include <iostream>
using namespace std;
#include <stdio.h>
// Compile OTL 4.0/ODBC in Windows. Informix CLI uses the
// regular ODBC header files in Windows
#define OTL_ODBC
// Uncomment the #defines below in Linux / Unix
//#define OTL_ODBC_UNIX
//#define OTL_INFORMIX_CLI
#include <otlv4.h> // include the OTL 4.0 header file
otl_connect db; // connect object
void select()
{
otl_stream i(1, // buffer size
"select * from test_tab",
// SELECT statement
db // connect object
);
// create select stream
otl_column_desc* desc;
int desc_len;
desc=i.describe_select(desc_len);
for(int n=0;n<desc_len;++n){
cout<<"========== COLUMN #"<<n+1<<" ==========="<<endl;
cout<<"name="<<desc[n].name<<endl;
cout<<"dbtype="<<desc[n].dbtype<<endl;
cout<<"otl_var_dbtype="<<desc[n].otl_var_dbtype<<endl;
cout<<"dbsize="<<desc[n].dbsize<<endl;
cout<<"scale="<<desc[n].scale<<endl;
cout<<"prec="<<desc[n].prec<<endl;
cout<<"nullok="<<desc[n].nullok<<endl;
}
}
int main()
{
otl_connect::otl_initialize(); // initialize Informix CLI environment
try{
db.rlogon("informix/tigger@informixsql"); // connect to Informix
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), f3 byte)"
); // create 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 Informix
return 0;
}
========== COLUMN #1 ===========
name=f1
dbtype=4
otl_var_dbtype=4
dbsize=10
scale=0
prec=10
nullok=1
========== COLUMN #2 ===========
name=f2
dbtype=12
otl_var_dbtype=1
dbsize=30
scale=0
prec=30
nullok=1
========== COLUMN #3 ===========
name=f3
dbtype=-4
otl_var_dbtype=10
dbsize=2147483647
scale=0
prec=2147483647
nullok=1
Copyright © 1996-2024, Sergei Kuchin, email: skuchin@gmail.com, skuchin@gmail.com/A>.