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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"><HTML><HEAD> <TITLE>OTL 4.0, Example 22 (Simple Insert/Select)</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 22 (Simple Insert/Select)</H1><H1><A NAME="example1"></A>Example 22 (Simple Insert/Select)</H1><P>This example demonstrates a typical error in otl_stream stream operations,when datatypes of a bind variable and an actual variable in the programdo not match.</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()// insert rows into table{ <A HREF="otl3_stream_class.htm">otl_stream</A> 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(){ <A HREF="otl3_stream_class.htm">otl_stream</A> i(50, // buffer size "select * from test_tab where f1>=:f<int> and f1<=:ff<int>*2", // SELECT statement db // connect object ); // create select stream float f1; char f2[31]; i<<8<<8; // assigning :f = 8; :ff = 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<A NAME="mismatch"></A> i>>f2>>f1; cout<<"f1="<<f1<<", f2="<<f2<<endl; } i<<4<<4; // assigning :f = 4, :ff = 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(){ <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 varchar(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.sqlstate<<endl; // print out SQLSTATE message 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><A HREF="otl3_exc_list.htm#32000">Incompatible data types in stream operation</A>select * from test_tab where f1>=? and f1<=?*2Column: 1<DOUBLE>, <A HREF="#mismatch">datatype in operator</A> <</>>: CHAR<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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