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<title>OTL 4.0, Example 284 (OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE,
PostgreSQL)</title>
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<h1>OTL 4.0, Example 284 (OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE)</h1>
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This example demonstrates a simple INSERT, SELECT, constant SQL
statements,
and #define
<br>
<a href="otl3_compile.htm#OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE">OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE.</a>.
<h2>
Source Code</h2>
<pre>#include <iostream><br>using namespace std;<br><br>#include <stdio.h></pre>
<pre>#define <a
href="file:///D%7C/oscl/vc/doc/otl4/otl3_compile.htm#OTL_ODBC">OTL_ODBC</a> // Compile OTL 4.0/ODBC<br>#define ODBCVER 0x0250 // ODBC Version # needs to be downgraded<br> // to 2.5 because the SQLite ODBC driver seems<br> // to run slower when ODBC 3.x functions<br> // used (performance is not as good as with<br> // ODBC 2.5 function calls)<br>#define <a
href="otl3_compile.htm#OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE">OTL_ADD_NULL_TERMINATOR_TO_STRING_SIZE<br></a>#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#no_commit">otl_stream</a> <br> o(10, // buffer size<br> "insert into test_tab values(:f1<int>,:f2<char[2]>)", <br> // SQL statement<br> db // connect object<br> );<br> for(int i=1;i<=100;++i){<br> o<<i<<"AB";<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>=:f<int> and f1<=:ff<int>*2",<br> // SELECT statement<br> db // connect object<br> ); <br> // create select stream<br> <br> float f1;<br> char f2[31];<br><br> i<<8<<8; // assigning :f = 8; :ff = 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> i>>f1>>f2;<br> cout<<"f1="<<f1<<", f2="<<f2<<endl;<br> }<br><br> i<<4<<4; // assigning :f = 4, :ff = 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@sqlite");<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 varchar(2))"<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.sqlstate<<endl; // print out SQLSTATE message<br> cerr<<p.var_info<<endl; // print out the variable that caused the error<br> }<br><br> db.logoff(); // disconnect from Oracle<br><br> return 0;<br><br>}</pre>
<h2>
Output</h2>
<pre>f1=8, f2=AB<br>f1=9, f2=AB<br>f1=10, f2=AB<br>f1=11, f2=AB<br>f1=12, f2=AB<br>f1=13, f2=AB<br>f1=14, f2=AB<br>f1=15, f2=AB<br>f1=16, f2=AB<br>f1=4, f2=AB<br>f1=5, f2=AB<br>f1=6, f2=AB<br>f1=7, f2=AB<br>f1=8, f2=AB<br><br><br><hr
width="100%"></pre>
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