📄 otl4_ex222.htm
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<title>OTL 4.0, Example 222 (std::string and CLOBs, Oracle 8/8i/9i)</title>
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<h1>
OTL 4.0, Example 222 (std::string and CLOBs, Oracle 8/8i/9i)</h1></center>
<h1>
Example 222 (std::string and CLOBs, Oracle 8/8i/9i)</h1>
<h2>
Source Code</h2>
<pre>#include <iostream>
#include <string>
using namespace std;</pre>
<pre>#define OTL_ORA8 // Compile OTL 4.0/OCI8
//#define OTL_ORA8I // Compile OTL 4.0/OCI8i
//#define OTL_ORA9I // Compile OTL 4.0/OCI9i
#define OTL_STL // Enable STL compatibily mode
#include <otlv4.h> // include the OTL 4.0 header file
<a href="otl3_connect_class.htm">otl_connect</a> db; // connect object
void insert()
// insert rows into table
{</pre>
<pre> string f2;
db.<a href="otl3_connect_class.htm#set_max_long_size">set_max_long_size</a>(70000); // set maximum long string size for connect object
<a href="otl3_stream_class.htm">otl_stream</a> o(1, // buffer size has to be set to 1 for operations with LOBs
"insert into test_tab values(:f1<int>,empty_clob()) "
"returning f2 into :f2<clob>",
// SQL statement
db // connect object
);
for(int i=1;i<=20;++i){
f2.assign(50001,' ');
for(int j=0;j<50000;++j)
f2[j]='*';
f2[50000]='?';
o<<i<<f2;
}
}
void select()
{
string f2;
db.<a href="otl3_connect_class.htm#set_max_long_size">set_max_long_size</a>(70000); // set maximum long string size for connect object
<a href="otl3_stream_class.htm">otl_stream</a> i(1, // buffer size needs to be set to 1 for operations with LOBs
"select * from test_tab where f1>=:f<int> and f1<=:f*2",
// SELECT statement
db // connect object
);
// create select stream
float f1;
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;
cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.length()-1]<<", len="
<<f2.length()<<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;
cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.length()-1]<<", len="
<<f2.length()<<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 clob)"
); // 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=*?, len=50001
f1=9, f2=*?, len=50001
f1=10, f2=*?, len=50001
f1=11, f2=*?, len=50001
f1=12, f2=*?, len=50001
f1=13, f2=*?, len=50001
f1=14, f2=*?, len=50001
f1=15, f2=*?, len=50001
f1=16, f2=*?, len=50001
f1=4, f2=*?, len=50001
f1=5, f2=*?, len=50001
f1=6, f2=*?, len=50001
f1=7, f2=*?, len=50001
f1=8, f2=*?, len=50001
<hr WIDTH="100%"></pre>
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