This example demonstrates simple INSERT and SELECT statements with the BLOB datatype as well as constant SQL statements.
#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_long_string f2(70000); // define long string variable db.set_max_long_size(70000); // set maximum long string size for connect object otl_stream o(1, // buffer size has to be set to 1 for operations with LOBs "insert into test_tab values(:f1<int>,empty_blob()) " "returning f2 into :f2<blob> ", // SQL statement db // connect object ); char tmp[32]; for(int i=1;i<=20;++i){ for(int j=0;j<50000;++j) f2[j]='*'; f2[50000]='?'; f2.set_len(50001); o<<i<<f2; } } void select() { otl_long_string f2(70000); // define long string variable db.set_max_long_size(70000); // set maximum long string size for connect object otl_stream i(10, // buffer size. To read BLOBs, it can be set to a size greater than 1 "select * from test_tab where f1>=:f<int> and f1<=:f*2", // SELECT statement db // connect object ); // create select stream float f1; i<<8; // assigning :f = 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>>f1>>f2; cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl; } 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[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<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 blob)" ); // 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 Oracle return 0; }
f1=8, f2=*?, len=50001 f1=9, f2=*?, len=50001 f1=10, f2=*?, len=50001 f1=11, f2=*?, len=50001 f1=12, f2=*?, len=50001 f1=13, f2=*?, len=50001 f1=14, f2=*?, len=50001 f1=15, f2=*?, len=50001 f1=16, f2=*?, len=50001 f1=4, f2=*?, len=50001 f1=5, f2=*?, len=50001 f1=6, f2=*?, len=50001 f1=7, f2=*?, len=50001 f1=8, f2=*?, len=50001
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.