?? otl4_ex587.htm
字號:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<html>
<head>
<title>OTL 4.0, Example 587 (Incompatible datatypes in stream
operation exception)</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 587<br>
</h1>
<h1 align="center">("Incompatible datatypes in stream operation"
exception)</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 program
do not match.</p>
<h2>Source Code</h2>
<pre>#include <iostream><br>using namespace std;<br><br>#include <stdio.h></pre>
<pre>#define <a href="otl3_compile.htm#OTL_ODBC_ENTERPRISEDB">OTL_ODBC_ENTERPRISEDB</a> // Compile OTL 4.0/EnterpriseDB-ODBC<br>// Uncomment the #define below when used in Linux / Unix<br>//#define OTL_ODBC_UNIX<br>#include <otlv4.h> // include the OTL 4.0 header file<br><br><a
href="otl3_connect_class.htm">otl_connect</a> db; // connect object<br><br>void insert()<br>// insert rows into table<br>{ <br> <a
href="otl3_stream_class.htm">otl_stream</a> o(50, // buffer size<br> "insert into test_tab values(:f1<int>,:f2<char[31]>)", <br> // SQL statement<br> db // connect object<br> );<br> char tmp[32];<br><br> for(int i=1;i<=100;++i){<br> sprintf(tmp,"Name%d",i);<br> o<<i<<tmp;<br> }<br>}<br><br>void select()<br>{ <br> <a
href="otl3_stream_class.htm">otl_stream</a> i(50, // buffer size<br> "select * from test_tab where f1>=:f11<int> and f1<=:f12<int>*2",<br> // SELECT statement<br> db // connect object<br> ); <br> // create select stream<br> <br> int f1;<br> char f2[31];<br><br> i<<8<<8; // assigning :f12 = 8, :f12 = 8<br> // SELECT automatically executes when all input variables are<br> // assigned. First portion of output rows is fetched to the buffer<br><br> while(!i.eof()){ // while not end-of-data<br> <a
name="incompatible"></a>i>>f2>>f1; // a typo: f2 instead of f1<br> cout<<"f1="<<f1<<", f2="<<f2<<endl;<br> }<br><br> i<<4<<4; // assigning :f11 = 4, :f12 = 4<br> // SELECT automatically executes when all input variables are<br> // assigned. First portion of output rows is fetched to the buffer<br><br> while(!i.eof()){ // while not end-of-data<br> i>>f1>>f2;<br> cout<<"f1="<<f1<<", f2="<<f2<<endl;<br> }<br><br>}<br><br>int main()<br>{<br> <a
href="otl3_connect_class.htm">otl_connect::otl_initialize</a>(); // initialize ODBC environment<br> try{<br><br> db.rlogon("scott/tiger@edbsql"); // connect to EDB<br><br> <a
href="otl3_const_sql.htm">otl_cursor::direct_exec<br></a> (<br> db,<br> "drop table test_tab",<br> otl_exception::disabled // disable OTL exceptions<br> ); // drop table<br><br> <a
href="otl3_const_sql.htm">otl_cursor::direct_exec<br></a> (<br> db,<br> "create table test_tab(f1 number, f2 varchar2(30))"<br> ); // create table<br><br> insert(); // insert records into table<br> select(); // select records from table<br><br> }<br><br> catch(<a
href="otl3_exception_class.htm">otl_exception</a>& p){ // intercept OTL exceptions<br> cerr<<p.msg<<endl; // print out error message<br> cerr<<p.stm_text<<endl; // print out SQL that caused the error<br> cerr<<p.var_info<<endl; // print out the variable that caused the error<br> }<br><br> db.logoff(); // disconnect from EDB<br><br> return 0;<br><br>}<br></pre>
<h2>Output</h2>
<pre><a href="otl3_exc_list.htm#32000">Incompatible data types in stream operation<br></a>select * from test_tab where f1>=:f and f1<=:f*2<br>Column: 1<DOUBLE>, <a
href="#incompatible">datatype in operator</a> <</>>: CHAR<br><br><br><br><br><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>
#define OTL_ODBC_SELECT_STM_EXECUTE_BEFORE_DESCRIBE
<a href="mailto:skuchin@gmail.com">skuchin@gmail.com/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></a>
<p></p>
<p><a href="mailto:skuchin@gmail.com"><i>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. </i></a></p>
<script type="text/javascript">
var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));
</script>
<script type="text/javascript">
var pageTracker = _gat._getTracker("UA-5456201-1");
pageTracker._trackPageview();
</script>
</body>
</html>
?? 快捷鍵說明
復制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號
Ctrl + =
減小字號
Ctrl + -