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<title>OTL 4.0, Example 421 (#define's OTL_DEFAULT_XXX_NULL_TO_VAL,
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<h1>OTL 4.0, Example 421 (#define's OTL_DEFAULT_XXX_NULL_TO_VAL, Sybase
SQL
Server)</h1>
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This example demonstrates how to use #define <a
href="otl3_compile.htm#OTL_DEFAULT_NUMERIC_NULL_TO_VAL">OTL_DEFAULT_NUMERIC_NULL_TO_VAL,</a><a
href="otl3_compile.htm#OTL_DEFAULT_DATETIME_NULL_TO_VAL">OTL_DEFAULT_DATETIME_NULL_TO_VAL</a>,
<a href="otl3_compile.htm#OTL_DEFAULT_STRING_NULL_TO_VAL">OTL_DEFAULT_STRING_NULL_TO_VAL,</a><a
href="otl3_compile.htm#OTL_DEFAULT_CHAR_NULL_TO_VAL">OTL_DEFAULT_CHAR_NULL_TO_VAL.</a>,
which allow the user to default NULLs to some values.
<h2>Source Code</h2>
<pre>#include <iostream><br>using namespace std;<br><br>#include <stdio.h></pre>
<pre>#define OTL_ODBC_UNIX // Compile OTL 4.0/ODBC<br><br>// Default "numeric" NULLs to (-1)<br>#define <a
href="otl3_compile.htm#OTL_DEFAULT_NUMERIC_NULL_TO_VAL">OTL_DEFAULT_NUMERIC_NULL_TO_VAL</a> (-1)<br><br>// Default "datetime" NULLs to otl_datetime(2000,1,1,0,0,0)<br>#define <a
href="otl3_compile.htm#OTL_DEFAULT_DATETIME_NULL_TO_VAL">OTL_DEFAULT_DATETIME_NULL_TO_VAL</a> otl_datetime(2000,1,1,0,0,0)<br><br>// Default "string" NULLs to "***NULL***"<br>#define <a
href="otl3_compile.htm#OTL_DEFAULT_STRING_NULL_TO_VAL">OTL_DEFAULT_STRING_NULL_TO_VAL</a> "***NULL***"<br><br>// Default "char" NULLs to '*'<br>#define <a
href="otl3_compile.htm#OTL_DEFAULT_CHAR_NULL_TO_VAL">OTL_DEFAULT_CHAR_NULL_TO_VAL</a> '*'<br><br>#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">otl_stream</a> o(50, // buffer size<br> "insert into test_tab "<br> "values(:f1<float>,:f2<char[31]>,NULL,:f4<timestamp>)", <br> // SQL statement<br> db // connect object<br> );<br> char tmp[32];<br> otl_datetime f4(2001,2,24,13,21,11);<br><br> for(int i=1;i<=100;++i){<br> sprintf(tmp,"Name%d",i);<br> if(i==10)<br> o<<(float)i<<otl_null()<<otl_null();<br> else<br> o<<(float)i<<tmp<<f4;<br> }<br><br>}<br><br>void select()<br>{ <br> <a
href="otl3_stream_class.htm">otl_stream</a> i(50, // buffer size<br> "select f1,f2,f2 f22,f3,f4 "<br> "from test_tab "<br> "where f1>=:f11<int> and f1<=:f12<int>*2",<br> // SELECT statement<br> db // connect object<br> ); <br> // create select stream<br> <br> float f1;<br> char f2[31];<br> char f22;<br> int f3;<br> otl_datetime f4;<br><br><br> <br> i<<8<<8; // assigning :f11 = 8, :f12=8<br> // SELECT automatically executes when all input variables are<br> // assigned. First portion of output rows is fetched to the buffer<br><br> cout<<"=====> Fetching rows and printing out default values instead of NULLs"<<endl;<br> while(!i.eof()){ // while not end-of-data<br> i>>f1;<br> cout<<"f1="<<f1<<", ";<br> i>>f2;<br> cout<<"f2="<<f2<<", ";<br> i>>f22;<br> cout<<"f22="<<f22<<", ";<br> i>>f3;<br> cout<<"f3="<<f3<<", ";<br> i>>f4;<br> cout<<"f4="<<f4.month<<"/"<br> <<f4.day<<"/"<br> <<f4.year<<" "<br> <<f4.hour<<":"<br> <<f4.minute<<":"<br> <<f4.second;<br> cout<<endl;<br> }<br><br> i<<8<<8; // assigning :f11 = 8, :f12=8<br> cout<<"=====> Fetching rows and printing out NULLs"<<endl;<br> while(!i.eof()){ // while not end-of-data<br> i>>f1;<br> if(i.is_null())<br> cout<<"f1=NULL, ";<br> else<br> cout<<"f1="<<f1<<", ";<br> i>>f2;<br> if(i.is_null())<br> cout<<"f2=NULL, ";<br> else<br> cout<<"f2="<<f2<<", ";<br> i>>f22;<br> if(i.is_null())<br> cout<<"f22=NULL, ";<br> else<br> cout<<"f22="<<f22<<", ";<br> i>>f3;<br> if(i.is_null())<br> cout<<"f3=NULL, ";<br> else<br> cout<<"f3="<<f3<<", ";<br> i>>f4;<br> if(i.is_null())<br> cout<<"f4=NULL,";<br> else<br> cout<<"f4="<<f4.month<<"/"<br> <<f4.day<<"/"<br> <<f4.year<<" "<br> <<f4.hour<<":"<br> <<f4.minute<<":"<br> <<f4.second;<br> cout<<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/tigger@sybsql"); // connect to MS SQL Server<br><br> <a
href="otl3_const_sql.htm">otl_cursor::direct_exec<br></a> (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> (db,<br> "create table test_tab(f1 int, f2 varchar(30), f3 int, f4 datetime)"<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.var_info<<endl; // print out the variable that caused the error<br> }<br><br> db.logoff(); // disconnect from MS SQL Server<br><br> return 0;<br><br>}</pre>
<h2>
Output</h2>
<pre>=====> Fetching rows and printing out default values instead of NULLs<br>f1=8, f2=Name8, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=9, f2=Name9, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=10, f2=***NULL***, f22=*, f3=-1, f4=1/1/2000 0:0:0<br>f1=11, f2=Name11, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=12, f2=Name12, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=13, f2=Name13, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=14, f2=Name14, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=15, f2=Name15, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>f1=16, f2=Name16, f22=N, f3=-1, f4=2/24/2001 13:21:11<br>=====> Fetching rows and printing out NULLs<br>f1=8, f2=Name8, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=9, f2=Name9, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=10, f2=NULL, f22=NULL, f3=NULL, f4=NULL,<br>f1=11, f2=Name11, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=12, f2=Name12, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=13, f2=Name13, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=14, f2=Name14, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=15, f2=Name15, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br>f1=16, f2=Name16, f22=N, f3=NULL, f4=2/24/2001 13:21:11<br><br><hr
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