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<TITLE>OTL 4.0, Example 97 (otl_value<T>, Oracle 7)</TITLE>
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<H1 ALIGN=CENTER>OTL 4.0, Example 97 (otl_value<T>, Oracle 7)</H1>
<H1>Example 97 (otl_value<T>, Oracle 7)</H1>
<P>This example demonstrates OTL streams and <A HREF="otl3_value.htm">otl_value<T></A>.
</P>
<H2>Source Code</H2>
<PRE>#include <iostream>
#include <string></PRE>
<PRE>#define OTL_ORA7 // Compile OTL 4.0/OCI7
#define OTL_STL // Turn on STL features and otl_value<T>
#define OTL_ANSI_CPP // Turn on ANSI C++ typecasts
#include <otlv4.h> // include the OTL 4.0 header file
using namespace std;
<A HREF="otl3_connect_class.htm">otl_connect</A> db; // connect object
void insert()
// insert rows into table
{
<A HREF="otl3_stream_class.htm">otl_stream</A> o(50, // buffer size
"insert into test_tab "
"values(:f1<int>,:f2<char[31]>,:f3<timestamp>)",
// SQL statement
db // connect object
);
<A HREF="otl3_value.htm">otl_value</A><string> f2; // otl_value container of STL string
<A HREF="otl3_value.htm">otl_value</A><<A HREF="otl3_stream_class.htm#otl_datetime">otl_datetime</A>> f3; // container of otl_datetime
for(int i=1;i<=100;++i){
if(i%2==0)
f2="NameXXX";
else
f2=otl_null(); // Assign otl_null() to f2
if(i%3==0){
// Assign a value to f3 via the .v field directly
f3.v.year=2001;
f3.v.month=1;
f3.v.day=1;
f3.v.hour=13;
f3.v.minute=10;
f3.v.second=5;
f3.set_non_null(); // Set f3 as a "non-NULL"
}else
f3.set_null(); // Set f3 as null via .set_null() function
o<<i<<f2<<f3;
}
}
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<=:f*2",
// SELECT statement
db // connect object
);
// create select stream
int f1;
<A HREF="otl3_value.htm">otl_value</A><string> f2;
<A HREF="otl3_value.htm">otl_value</A><<A HREF="otl3_stream_class.htm#otl_datetime">otl_datetime</A>> f3;
i<<8; // assigning :f = 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
i>>f1>>f2>>f3;
cout<<"f1="<<f1<<", f2="<<f2<<", f3="<<f3<<endl;
}
i<<4; // assigning :f = 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>>f3;
cout<<"f1="<<f1<<", f2="<<f2<<", f3="<<f3<<endl;
}
}
int main()
{
<A HREF="otl3_connect_class.htm">otl_connect::otl_initialize</A>(); // initialize OCI environment
try{
db.rlogon("scott/tiger"); // connect to Oracle
<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 number, f2 varchar2(30), f3 date)"
); // 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.var_info<<endl; // print out the variable that caused the error
}
db.logoff(); // disconnect from Oracle
return 0;
}
</PRE>
<H2>Output</H2>
<PRE>f1=8, f2=NameXXX, f3=NULL
f1=9, f2=NULL, f3=1/1/2001 13:10:5
f1=10, f2=NameXXX, f3=NULL
f1=11, f2=NULL, f3=NULL
f1=12, f2=NameXXX, f3=1/1/2001 13:10:5
f1=13, f2=NULL, f3=NULL
f1=14, f2=NameXXX, f3=NULL
f1=15, f2=NULL, f3=1/1/2001 13:10:5
f1=16, f2=NameXXX, f3=NULL
f1=4, f2=NameXXX, f3=NULL
f1=5, f2=NULL, f3=NULL
f1=6, f2=NameXXX, f3=1/1/2001 13:10:5
f1=7, f2=NULL, f3=NULL
f1=8, f2=NameXXX, f3=NULL
<HR WIDTH="100%"></PRE>
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<P>Copyright © 1996, 2008, Sergei Kuchin, email: <A HREF="mailto:skuchin@aceweb.com">skuchin@aceweb.com</A>,
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