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<!DOCTYPE html PUBLIC "-//w3c//dtd html 4.0 transitional//en"><html><head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <meta name="Author" content="Sergei Kuchin"> <meta name="GENERATOR" content="Mozilla/4.75 [en] (Win98; U) [Netscape]"> <meta name="KeyWords" content="OTL, Oracle, ODBC, DB2, CLI, database API, C++, Template Library"> <title>OTL 4.0, Example 444 (Insert/Update/Select with Sybase IMAGEin stream mode, without otl_lob_stream::set_len())</title></head><body><center><h1>OTL 4.0, Example 444 (Insert/Update/Select with Sybase IMAGE instreammode, without otl_lob_stream::set_len())</h1></center>This example demonstrates INSERT, UPDATE, and SELECT statements withtheSybase IMAGE datatype in the <a href="otl3_lob_stream.htm">stream mode</a>,without otl_lob_stream::set_len() in OTL 4.0.138 and higher.<br><h2>Source Code</h2><pre>#include <iostream><br>using namespace std;<br><br>#include <stdio.h></pre><pre>#define OTL_ODBC_UNIX // Compile OTL 4.0/DB2-CLI<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>{<a href="otl3_long_string.htm">otl_long_string</a> f2(6000); // define long string variable<br> <a href="otl3_stream_class.htm">otl_stream</a> o; // defined an otl_stream variable<br> o.<a href="otl3_stream_class.htm#set_lob_stream_mode">set_lob_stream_mode</a>(true); // set the "lob stream mode" flag<br> o.<a href="otl3_stream_class.htm#open">open</a>(1, // buffer size has to be set to 1 for operations with LOBs<br> "insert into test_tab values(:f1<int>,:f2<raw_long>, "<br> ":f3<raw_long>) ",<br> // SQL statement<br> db // connect object<br> );<br> o.<a href="otl3_stream_class.htm#set_commit">set_commit</a>(0); // setting stream "auto-commit" to "off". It is required<br> // when LOB stream mode is used.</pre><pre> int i,j;<br> <a href="otl3_lob_stream.htm">otl_lob_stream</a> lob; // LOB stream for reading/writing unlimited number<br> // of bytes regardless of the buffer size.<br> <a href="otl3_lob_stream.htm">otl_lob_stream</a> lob2; // LOB stream for reading/writing unlimited number<br> // of bytes regardless of the buffer size.<br><br> for(i=1;i<=20;++i){<br> o<<i;<br> o<a href="otl3_stream_class.htm#stream_write_lob"><<</a>lob; // Initialize otl_lob_stream by writing it<br> // into otl_stream.<br> o<a href="otl3_stream_class.htm#stream_write_lob"><<</a>lob2; // Initialize otl_lob_stream by writing it<br> // into otl_stream.<br><br> for(j=0;j<5000;++j)<br> f2[j]='*';<br> f2[5000]='?';<br> f2.<a href="otl3_long_string.htm#set_len">set_len</a>(5001);<br><br>// OTL 4.0.138 and higher does not require the LOB's total length to be <br>// set beforehand. Instead, otl_long_string::last_piece can be used.<br>// lob.<a href="otl3_lob_stream.htm#set_len">set_len</a>(5001+2123); // setting the total size of<br>// // the IMAGE to be written.<br> <br> lob<a href="otl3_lob_stream.htm#write"><<</a>f2; // writing first chunk of the IMAGE into lob<br><br><br> f2[2122]='?';<br> f2.set_len(2123); // setting the size of the second chunk<br><br> lob<<f2; // writing the second chunk of the IMAGE into lob<br> lob.<a href="otl3_lob_stream.htm">close</a>(); // closing the otl_lob_stream<br><br> for(j=0;j<5000;++j)<br> f2[j]='*';<br> f2[5000]='?';<br> f2.<a href="otl3_long_string.htm#set_len">set_len</a>(5001);<br> lob2.<a href="otl3_lob_stream.htm#set_len">set_len</a>(5001+2123); // setting the total size of<br> // the IMAGE to be written.<br> <br> lob2<a href="otl3_lob_stream.htm#write"><<</a>f2; // writing first chunk of the IMAGE into lob<br><br> f2[2122]='?';<br> f2.set_len(2123); // setting the size of the second chunk<br><br> lob2<<f2; // writing the second chunk of the IMAGE into lob<br> lob2.<a href="otl3_lob_stream.htm">close</a>(); // closing the otl_lob_stream<br><br> }<br><br> db.commit(); // committing transaction.<br>}</pre><pre>void update()<br>// insert rows in table<br>{</pre><pre> <a href="otl3_long_string.htm">otl_long_string</a> f2(6200); // define long string variable<br><br> <a href="otl3_stream_class.htm">otl_stream</a> o; // defined an otl_stream variable<br> o.<a href="otl3_stream_class.htm#set_lob_stream_mode">set_lob_stream_mode</a>(true); // set the "lob stream mode" flag<br> o.<a href="otl3_stream_class.htm#open">open</a>(1, // buffer size has to be set to 1 for operations with LOBs<br> "update test_tab "<br> " set f2=:f2<raw_long> "<br> "where f1=:f1<int> ",<br> // SQL statement<br> db // connect object<br> );<br><br> <a href="otl3_lob_stream.htm">otl_lob_stream</a> lob;<br><br> o.<a href="otl3_stream_class.htm#set_commit">set_commit</a>(0); // setting stream "auto-commit" to "off". <br><br><br> for(int j=0;j<6000;++j){<br> f2[j]='#';<br> }<br><br> f2[6000]='?';<br> f2.<a href="otl3_long_string.htm#set_len">set_len</a>(6001);<br><br> o<a href="otl3_stream_class.htm#stream_write_lob"><<</a>lob; // Initialize otl_lob_stream by writing it<br> // into otl_stream.<br> o<<5;<br><br>// OTL 4.0.138 and higher does not require the LOB's total length to be <br>// set beforehand. Instead, otl_long_string::last_piece can be used.<br>// lob.<a href="otl3_lob_stream.htm#set_len">set_len</a>(6001*4); // setting the total size of of the IMAGE to be written<br><br> for(int i=1;i<=4;++i)<br> lob<a href="otl3_lob_stream.htm#write"><<</a>f2; // writing chunks of the IMAGE into the otl_lob_stream<br><br> lob.<a href="otl3_lob_stream.htm#close">close</a>(); // closing the otl_lob_stream<br><br> db.commit(); // committing transaction<br><br>}<br><br>void select()<br>{ <br> <a href="otl3_long_string.htm">otl_long_string</a> f2(3000); // define long string variable<br><br> <a href="otl3_stream_class.htm">otl_stream</a> i; // defined an otl_stream variable<br> i.<a href="otl3_stream_class.htm#set_lob_stream_mode">set_lob_stream_mode</a>(true); // set the "lob stream mode" flag<br> i.<a href="otl3_stream_class.htm#open">open</a>(1, // buffer size. To read IMAGEs, it should be set to 1<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> <a href="otl3_lob_stream.htm">otl_lob_stream</a> lob; // Stream for reading IMAGE<br> <a href="otl3_lob_stream.htm">otl_lob_stream</a> lob2; // Stream for reading IMAGE<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;<br> cout<<"f1="<<f1<<endl;<br> i<a href="otl3_stream_class.htm#stream_read_lob">>></a>lob; // initializing LOB stream by reading the IMAGE reference <br> // into the otl_lob_stream from the otl_stream.<br> i<a href="otl3_stream_class.htm#stream_read_lob">>></a>lob2; // initializing LOB stream by reading the IMAGE reference <br> // into the otl_lob_stream from the otl_stream.<br> int n=0;<br> while(!lob.<a href="otl3_lob_stream.htm#eof">eof</a>()){ // read while not "end-of-file" -- end of IMAGE<br> ++n;<br> lob<a href="otl3_lob_stream.htm#read">>></a>f2; // reading a chunk of IMAGE<br> cout<<" chunk #"<<n;<br> cout<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;<br> }<br> lob.<a href="otl3_lob_stream.htm#close">close</a>(); // closing the otl_lob_stream.<br> n=0;<br> while(!lob2.<a href="otl3_lob_stream.htm#eof">eof</a>()){ // read while not "end-of-file" -- end of IMAGE<br> ++n;<br> lob2<a href="otl3_lob_stream.htm#read">>></a>f2; // reading a chunk of IMAGE<br> cout<<" chunk #"<<n;<br> cout<<", f3="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;<br> }<br> lob2.<a href="otl3_lob_stream.htm#close">close</a>(); // closing the otl_lob_stream. <br> <br> }<br><br>}<br><br>int main()<br>{<br> <a href="otl3_connect_class.htm">otl_connect::otl_initialize</a>(); // initialize the environment<br> try{<br><br> db.rlogon("scott/tigger@sybsql"); // connect to the database<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 int, f2 image, f3 image)"<br> ); // create table<br><br> insert(); // insert records into table<br> update(); // update records in 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.sqlstate<<endl; // print out SQLSTATE <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 the database<br><br> return 0;<br><br>}</pre><h2>Output</h2><pre>f1=4<br> chunk #1, f2=**, len=3000<br> chunk #2, f2=**, len=3000<br> chunk #3, f2=*?, len=1124<br> chunk #1, f3=**, len=3000<br> chunk #2, f3=**, len=3000<br> chunk #3, f3=*?, len=1124<br>f1=5<br> chunk #1, f2=##, len=3000<br> chunk #2, f2=##, len=3000<br> chunk #3, f2=?#, len=3000<br> chunk #4, f2=##, len=3000<br> chunk #5, f2=##, len=3000<br> chunk #6, f2=##, len=3000<br> chunk #7, f2=##, len=3000<br> chunk #8, f2=##, len=3000<br> chunk #9, f2=#?, len=4<br> chunk #1, f3=**, len=3000<br> chunk #2, f3=**, len=3000<br> chunk #3, f3=*?, len=1124<br>f1=6<br> chunk #1, f2=**, len=3000<br> chunk #2, f2=**, len=3000<br> chunk #3, f2=*?, len=1124<br> chunk #1, f3=**, len=3000<br> chunk #2, f3=**, len=3000<br> chunk #3, f3=*?, len=1124<br>f1=7<br> chunk #1, f2=**, len=3000<br> chunk #2, f2=**, len=3000<br> chunk #3, f2=*?, len=1124<br> chunk #1, f3=**, len=3000<br> chunk #2, f3=**, len=3000<br> chunk #3, f3=*?, len=1124<br>f1=8<br> chunk #1, f2=**, len=3000<br> chunk #2, f2=**, len=3000<br> chunk #3, f2=*?, len=1124<br> chunk #1, f3=**, len=3000<br> chunk #2, f3=**, len=3000<br> chunk #3, f3=*?, len=1124<br><br><hr width="100%"></pre><center><a href="otl3_examples.htm">Examples</a> <a href="otl3.htm">Contents</a><a href="home.htm">GoHome</a></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@gmail.com<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><i>Permission to use, copy, modify and redistribute this documentforany purpose is hereby granted without fee, provided that the abovecopyrightnotice appear in all copies.</i></p><script type="text/javascript">var gaJsHost = (("https:" == document.location.protocol) ? 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