OTL 4.0, Example 771 (OTL stream, std::tuple<>, and std::array<char,...>)

This example demonstrates how to use OTL stream with std::tuple<> template.

Source Code

#include <iostream>
using namespace std;

#include <stdio.h>
#define OTL_DB2_CLI // Compile OTL 4.0/DB2 CLI
#define OTL_STREAM_WITH_STD_TUPLE_ON
#define OTL_STREAM_WITH_CHAR_ARRAY_ON
#if !defined(OTL_CPP_14_ON)
#define OTL_CPP_14_ON
#endif
#include <otlv4.h> // include the OTL 4 header file

otl_connect db; // connect object

using Tuple=std::tuple<int,std:array<char,32>>;

void insert()
// insert rows into table
{
otl_stream o(50, // buffer size
"insert into test_tab values(:f<int>,:f2<char[31]>)",
// SQL statement
db // connect object
);
Tuple t;

for(int i=1;i<=100;++i){
#if defined(_MSC_VER) && (_MSC_VER >= 1400) // VC++ 8.0 or higher
sprintf_s(std::get<1>(t).data(),std::get<1>(t).size(),"Name%d",i);
#else
sprintf(std::get<1>(t).data(),"Name%d",i);
#endif
std::get<0>(t)=i;
o<<t;
}

}

void select()
{
otl_stream i(50, // buffer size
"select * from test_tab where f1>=:f1_1<int> and f1<=:f1_2<int>*2",
// SELECT statement
db // connect object
);
// create select stream

Tuple t;
int f1;
char f2[32];

i<<8<<8;

// C++11 range-for loop can be used with OTL streams
for(auto& it : i){
it>>t;
cout<<"f1="<<std::get<0>(t)<<", f2="<<std::get<1>(t).data()<<endl;
}

i<<4<<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<<endl;
}


}

int main()
{
otl_connect::otl_initialize(); // initialize database environment
try{

db.rlogon("scott/tiger@db2sql"); // connect to the database

otl_cursor::direct_exec
(
db,
"drop table test_tab",
otl_exception::disabled // disable OTL exceptions
); // drop table

otl_cursor::direct_exec
(
db,
"create table test_tab(f1 int, f2 varchar(31))"
); // create table

insert(); // insert records into table
select(); // select records from table

}

catch(otl_exception& 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 the database

return 0;

}

Output

f1=8, f2=Name8
f1=9, f2=Name9
f1=10, f2=Name10
f1=11, f2=Name11
f1=12, f2=Name12
f1=13, f2=Name13
f1=14, f2=Name14
f1=15, f2=Name15
f1=16, f2=Name16
f1=4, f2=Name4
f1=5, f2=Name5
f1=6, f2=Name6
f1=7, f2=Name7
f1=8, f2=Name8

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Copyright 1996-2017, Sergei Kuchin, email: skuchin@gmail.com, skuchin@gmail.com .

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. THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.