# OTL 4.0, Example 169 (#define's OTL_DEFAULT_XXX_NULL_TO_VAL, Oracle 7/8/8i/9i)

# Example 169 (#define's OTL_DEFAULT_XXX_NULL_TO_VAL, Oracle 8/8i/9i)

This example demonstrates how to use #define OTL_DEFAULT_NUMERIC_NULL_TO_VAL,OTL_DEFAULT_DATETIME_NULL_TO_VAL, OTL_DEFAULT_STRING_NULL_TO_VAL,OTL_DEFAULT_CHAR_NULL_TO_VAL., which allow the user to default NULLs to some values.

## Source Code

    #include <iostream>
    using namespace std;

    #include <stdio.h>

    #define OTL_ORA8I // Compile OTL 4.0/OCI8i
    //#define OTL_ORA7 // Uncomment this line to compile OTL 4.0/OCI7
    //#define OTL_ORA8 // Uncomment this line to compile OTL 4.0/OCI8
    //#define OTL_ORA9I // Uncomment this line to compile OTL 4.0/OCI9i

    // Default "numeric" NULLs to (-1)
    #define OTL_DEFAULT_NUMERIC_NULL_TO_VAL (-1)

    // Default "datetime" NULLs to otl_datetime(2000,1,1,0,0,0)
    #define OTL_DEFAULT_DATETIME_NULL_TO_VAL otl_datetime(2000,1,1,0,0,0)

    // Default "string" NULLs to "***NULL***"
    #define OTL_DEFAULT_STRING_NULL_TO_VAL "***NULL***"

    // Default "char" NULLs to '*'
    #define OTL_DEFAULT_CHAR_NULL_TO_VAL '*'

    #include <otlv4.h> // include the OTL 4.0 header file

    otl_connect db; // connect object

    void insert()
    // insert rows into table
    {
     otl_stream o(50, // buffer size
                  "insert into test_tab "
                  "values(:f1<float>,:f2<char[31]>,NULL,:f4<timestamp>)",
                     // SQL statement
                  db // connect object
                 );
     char tmp[32];
     otl_datetime f4(2001,2,24,13,21,11);

     for(int i=1;i<=100;++i){
      sprintf(tmp,"Name%d",i);
      if(i==10)
       o<<(float)i<<otl_null()<<otl_null();
      else
       o<<(float)i<<tmp<<f4;
     }

    }

    void select()
    {
     otl_stream i(50, // buffer size
                  "select f1,f2,f2 f22,f3,f4 "
                   "from test_tab "
                   "where f1>=:f11<int> and f1<=:f12<int>*2",
                     // SELECT statement
                  db // connect object
                 );
       // create select stream

     float f1;
     char f2[31];
     char f22;
     int f3;
     otl_datetime f4;

     i<<8<<8; // assigning :f11 = 8, :f12=8
       // SELECT automatically executes when all input variables are
       // assigned. First portion of output rows is fetched to the buffer

     cout<<"=====> Fetching rows and printing out default values instead of NULLs"<<endl;
     while(!i.eof()){ // while not end-of-data
      i>>f1;
      cout<<"f1="<<f1<<", ";
      i>>f2;
      cout<<"f2="<<f2<<", ";
      i>>f22;
      cout<<"f22="<<f22<<", ";
      i>>f3;
      cout<<"f3="<<f3<<", ";
      i>>f4;
      cout<<"f4="<<f4.month<<"/"
          <<f4.day<<"/"
          <<f4.year<<" "
          <<f4.hour<<":"
          <<f4.minute<<":"
          <<f4.second;
      cout<<endl;
     }

     i<<8<<8; // assigning :f11 = 8, :f12=8
     cout<<"=====> Fetching rows and printing out NULLs"<<endl;
     while(!i.eof()){ // while not end-of-data
      i>>f1;
      if(i.is_null())
       cout<<"f1=NULL, ";
      else
       cout<<"f1="<<f1<<", ";
      i>>f2;
      if(i.is_null())
       cout<<"f2=NULL, ";
      else
       cout<<"f2="<<f2<<", ";
      i>>f22;
      if(i.is_null())
       cout<<"f22=NULL, ";
      else
       cout<<"f22="<<f22<<", ";
      i>>f3;
      if(i.is_null())
       cout<<"f3=NULL, ";
      else
       cout<<"f3="<<f3<<", ";
      i>>f4;
      if(i.is_null())
       cout<<"f4=NULL,";
      else
       cout<<"f4="<<f4.month<<"/"
           <<f4.day<<"/"
           <<f4.year<<" "
           <<f4.hour<<":"
           <<f4.minute<<":"
           <<f4.second;
      cout<<endl;
     }

    }

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

      db.rlogon("scott/tiger"); // connect to Oracle

      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(30), f3 int, f4 date)"
        );  // 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 Oracle

     return 0;

    }

## Output

    =====> Fetching rows and printing out default values instead of NULLs
    f1=8, f2=Name8, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=9, f2=Name9, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=10, f2=***NULL***, f22=*, f3=-1, f4=1/1/2000 0:0:0
    f1=11, f2=Name11, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=12, f2=Name12, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=13, f2=Name13, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=14, f2=Name14, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=15, f2=Name15, f22=N, f3=-1, f4=2/24/2001 13:21:11
    f1=16, f2=Name16, f22=N, f3=-1, f4=2/24/2001 13:21:11
    =====> Fetching rows and printing out NULLs
    f1=8, f2=Name8, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=9, f2=Name9, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=10, f2=NULL, f22=NULL, f3=NULL, f4=NULL,
    f1=11, f2=Name11, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=12, f2=Name12, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=13, f2=Name13, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=14, f2=Name14, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=15, f2=Name15, f22=N, f3=NULL, f4=2/24/2001 13:21:11
    f1=16, f2=Name16, f22=N, f3=NULL, f4=2/24/2001 13:21:11

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