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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"><HTML><HEAD> <TITLE>OTL 4.0, Example 30 (Oracle and LONG column)</TITLE> <META NAME="Author" CONTENT="Sergei Kuchin"> <META NAME="GENERATOR" CONTENT="Mozilla/3.03Gold (Win95; I) [Netscape]"> <META NAME="KeyWords" CONTENT="OTL, Oracle, ODBC, DB2, CLI, database API, C++, Template Library"></HEAD><BODY><H1 ALIGN=CENTER>OTL 4.0, Example 30 (Oracle and LONG column)</H1><H1><A NAME="example1"></A>Example 30 (Oracle and LONG column)</H1><P>This example demonstrates simple INSERT and SELECT with Oracle and LONGcolumns.</P><H2>Source Code</H2><PRE>#include <iostream>using namespace std;#include <stdio.h></PRE><PRE>#define OTL_ODBC // Compile OTL 4.0/ODBC#include <otlv4.h> // include the OTL 4.0 header file<A HREF="otl3_connect_class.htm">otl_connect</A> db; // connect objectvoid insert(void)// insert rows into table{ <A HREF="otl3_long_string.htm">otl_long_string</A> f2(70000); // define long string variable db.<A HREF="otl3_connect_class.htm#set_max_long_size">set_max_long_size</A>(70000); // set maximum long string size for connect object <A HREF="otl3_stream_class.htm">otl_stream</A> o(1, // buffer size needs to be set to 1 for long strings "insert into test_tab values(:f1<int>,:f2<<A HREF="otl3_bind_variables.htm#varchar_long">varchar_long</A>>)", // SQL statement db // connect object ); for(int i=1;i<=20;++i){ for(int j=0;j<50000;++j) f2[j]='*'; f2[50000]='?'; f2.<A HREF="otl3_long_string.htm#set_len">set_len</A>(50001); o<<i<<f2; }}void select(void){ 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(1, // buffer size needs to be set to 1 "select * from test_tab where f1>=:f11<int> and f1<=:f12<int>*2", // SELECT statement db // connect object ); // create select stream int f1; i<<8<<8; // assigning :f11 = 8, :f12 = 8 // SELECT automatically executes when all input variables are // assigned. First portion of out 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<<4; // assigning :1 = 4, :2 = 4 // SELECT automatically re-executes when all input variables are // assigned. First portion of out 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; }}</PRE><PRE>int main(){ <A HREF="otl3_connect_class.htm">otl_connect::otl_initialize</A>(); // initialize ODBC environment try{ db.rlogon("UID=scott;PWD=tiger;DSN=my_db"); // connect to ODBC <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 int, f2 long)" ); // 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.sqlstate<<endl; // print out SQLSTATE message cerr<<p.var_info<<endl; // print out the variable that caused the error } db.logoff(); // disconnect from ODBC return 0;}</PRE><H2>Output</H2><PRE>f1=8, f2=*?, len=50001f1=9, f2=*?, len=50001f1=10, f2=*?, len=50001f1=11, f2=*?, len=50001f1=12, f2=*?, len=50001f1=13, f2=*?, len=50001f1=14, f2=*?, len=50001f1=15, f2=*?, len=50001f1=16, f2=*?, len=50001f1=4, f2=*?, len=50001f1=5, f2=*?, len=50001f1=6, f2=*?, len=50001f1=7, f2=*?, len=50001f1=8, f2=*?, len=50001<HR WIDTH="100%"></PRE><CENTER><P><A HREF="otl3_examples.htm">Examples</A> <A HREF="otl3.htm">Contents</A><A HREF="home.htm">Go Home</A> </P></CENTER><P>Copyright © 1996, 2008, Sergei Kuchin, email: <A HREF="mailto:skuchin@aceweb.com">skuchin@aceweb.com</A>,<A HREF="mailto:skuchin@gmail.com">skuchin@yahogmail</A><SCRIPT Language="JavaScript"><!-- hide from old browsers var modDate = new Date(document.lastModified) document.write("<i> Last Updated:</i> " + (modDate.getMonth()+1) + "/" + modDate.getDate() + "/" + "0"+(modDate.getYear())%100+"."); //--> </SCRIPT>.</P><P><I>Permission to use, copy, modify and redistribute this document forany purpose is hereby granted without fee, provided that the above copyrightnotice appear in all copies. </I></P></BODY></HTML>⌨️ 快捷键说明
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