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📄 otl4_ex285.htm

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  <title>OTL 4.0, Example 285 (Simple Unicode Insert/Select for both
VARCHAR2 and NVARCHAR2 at the same time)</title>
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<h1>OTL 4.0, Example 285 (Simple Unicode Insert/Select for both
VARCHAR2 and NVARCHAR2 at the same time)</h1>
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<h1>
Example 285 (Simple Unicode Insert/Select for both VARCHAR2 and
NVARCHAR2 at the same time)</h1>
This example demonstrates a simple Unicode INSERT, SELECT for both
VARCHAR and NVARCHAR2 at the same time.
<h2>Source Code</h2>
<pre>#include &lt;iostream&gt;<br>using namespace std;<br><br>#include &lt;stdio.h&gt;</pre>
<pre>#define OTL_ORA8I // Compile OTL 4.0/OCI8i<br>//#define OTL_ORA9I // Compile OTL 4.0/OCI9i<br>//#define OTL_ORA10G // Compile OTL 4.0/OCI10g<br>#define <a
 href="otl3_compile.htm#OTL_UNICODE">OTL_UNICODE</a> // Enable Unicode OTL for OCI8i<br>#include &lt;otlv4.h&gt; // 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>{&nbsp;<br>&nbsp;<a
 href="otl3_stream_class.htm">otl_stream</a> o(50, // buffer size<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "insert into test_tab "<br>               "values(:f1&lt;<a
 href="otl3_bind_variables.htm#int">int</a>&gt;,:f2&lt;<a
 href="otl3_bind_variables.htm#char">char</a>[31]&gt;,:f3&lt;<a
 href="otl3_bind_variables.htm#nchar">nchar</a>[31]&gt;)",&nbsp;<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // SQL statement<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; db // connect object<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; );<br>&nbsp;char tmp[32];<br>&nbsp;unsigned short tmp2[31]; // Null terminated Unicode character array.<br><br>&nbsp;for(int i=1;i&lt;=100;++i){<br>&nbsp; sprintf(tmp,"Name%d",i);<br>&nbsp; unsigned short* c2=tmp2;<br>&nbsp; char* c1=tmp;<br>// Unicode's first 128 characters are ASCII (0..127), so<br>// all is needed for converting ASCII into Unicode is as follows:<br>&nbsp; while(*c1){<br>&nbsp;&nbsp; *c2=(unsigned char)*c1;<br>&nbsp;&nbsp; ++c1; ++c2;&nbsp;&nbsp;&nbsp;<br>&nbsp; }&nbsp;&nbsp;<br>&nbsp; *c2=0; // target Unicode string is null terminated,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // only the null terminator is a two-byte character,&nbsp;<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // not one-byte<br>&nbsp; o&lt;&lt;i;<br>&nbsp; o<a
 href="otl3_stream_class.htm#unicode_unsigned_char_write">&lt;&lt;</a>(unsigned char*)tmp2;&nbsp;<br>&nbsp;&nbsp; // overloaded operator&lt;&lt;(const unsigned char*) in the case of Unicode<br>&nbsp;&nbsp; // OTL accepts a pointer to a Unicode character array.<br>&nbsp;&nbsp; // operator&lt;&lt;(const unsigned short*) wasn't overloaded<br>&nbsp;&nbsp; // in order to avoid ambiguity in C++ type casting.<br>&nbsp; o<a
 href="otl3_stream_class.htm#unicode_unsigned_char_write">&lt;&lt;</a>(unsigned char*)tmp2;&nbsp;<br>&nbsp;}<br><br>}<br><br>void select()<br>{&nbsp;<br>&nbsp;<a
 href="otl3_stream_class.htm">otl_stream</a> i(50, // buffer size<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "select "<br>               "  f1, f2, "<br>               "  f3 :#3&lt;<a
 href="otl3_bind_variables.htm#nchar">nchar</a>[31]&gt; " <br>                 // override the default mapping of f3 (from char[]) <br>                 // to nchar[]<br>              "from test_tab "<br>              "where f1&gt;=:f&lt;int&gt; "<br>              "  and f1&lt;=:f*2",<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // SELECT statement<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; db // connect object<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; );&nbsp;<br>&nbsp;&nbsp; // create select stream<br>&nbsp;<br>&nbsp;int f1;<br>&nbsp;unsigned short f2[31];<br>&nbsp;unsigned short f3[31];<br><br>&nbsp;i&lt;&lt;4; // assigning :f = 4<br>&nbsp;&nbsp; // SELECT automatically executes when all input variables are<br>&nbsp;&nbsp; // assigned. First portion of output rows is fetched to the buffer<br><br>&nbsp;while(!i.eof()){ // while not end-of-data<br>&nbsp; i&gt;&gt;f1;<br>&nbsp; i<a
 href="otl3_stream_class.htm#unicode_unsigned_read">&gt;&gt;</a>(unsigned char*)f2;<br>&nbsp;&nbsp;&nbsp; // overloaded operator&gt;&gt;(unsigned char*) in the case of Unicode<br>&nbsp;&nbsp;&nbsp; // OTL accepts a pointer to a Unicode chracter array.<br>&nbsp;&nbsp;&nbsp; // operator&gt;&gt;(unsigned short*) wasn't overloaded&nbsp;<br>&nbsp;&nbsp;&nbsp; // in order to avoid ambiguity in C++ type casting.<br>&nbsp; i<a
 href="otl3_stream_class.htm#unicode_unsigned_read">&gt;&gt;</a>(unsigned char*)f3;<br>&nbsp; cout&lt;&lt;"f1="&lt;&lt;f1&lt;&lt;", f2=";<br>// Unicode's first 128 characters are ASCII, so in order<br>// to convert Unicode back to ASCII all is needed is<br>// as follows:<br>&nbsp;&nbsp; for(int j=0;f2[j]!=0;++j){<br>&nbsp;&nbsp;&nbsp;&nbsp; cout&lt;&lt;(char)f2[j];<br>&nbsp;&nbsp; }<br> &nbsp; cout&lt;&lt;", f3=";<br>&nbsp;&nbsp; for(int j2=0;f3[j2]!=0;++j2){<br>&nbsp;&nbsp;&nbsp;&nbsp; cout&lt;&lt;(char)f2[j2];<br>&nbsp;&nbsp; }<br>&nbsp;&nbsp; cout&lt;&lt;endl;<br>&nbsp;}<br><br>}<br><br>int main()<br>{<br>&nbsp;<a
 href="otl3_connect_class.htm">otl_connect::otl_initialize</a>(); // initialize OCI environment<br>&nbsp;try{<br><br>&nbsp; db.rlogon("scott/tiger"); // connect to Oracle<br><br>&nbsp; <a
 href="otl3_const_sql.htm">otl_cursor::direct_exec<br></a>&nbsp;&nbsp; (<br>&nbsp;&nbsp;&nbsp; db,<br>&nbsp;&nbsp;&nbsp; "drop table test_tab",<br>&nbsp;&nbsp;&nbsp; otl_exception::disabled // disable OTL exceptions<br>&nbsp;&nbsp; ); // drop table<br><br>&nbsp; <a
 href="otl3_const_sql.htm">otl_cursor::direct_exec<br></a>&nbsp;&nbsp; (<br>&nbsp;&nbsp;&nbsp; db,<br>&nbsp;&nbsp;&nbsp; "create table test_tab(f1 number, f2 varchar2(60), f3 nvarchar2(60))"<br>&nbsp;&nbsp;&nbsp; );&nbsp; // create table<br><br>&nbsp; insert(); // insert records into table<br>&nbsp; select(); // select records from table<br><br>&nbsp;}<br><br>&nbsp;catch(<a
 href="otl3_exception_class.htm">otl_exception</a>&amp; p){ // intercept OTL exceptions<br>&nbsp; cerr&lt;&lt;p.msg&lt;&lt;endl; // print out error message<br>&nbsp; cerr&lt;&lt;p.stm_text&lt;&lt;endl; // print out SQL that caused the error<br>&nbsp; cerr&lt;&lt;p.var_info&lt;&lt;endl; // print out the variable that caused the error<br>&nbsp;}<br><br>&nbsp;db.logoff(); // disconnect from Oracle<br><br>&nbsp;return 0;<br><br>}</pre>
<h2>
Output</h2>
<pre>f1=4, f2=Name4, f3=Name4<br>f1=5, f2=Name5, f3=Name5<br>f1=6, f2=Name6, f3=Name6<br>f1=7, f2=Name7, f3=Name7<br>f1=8, f2=Name8, f3=Name8<br><br><hr
 width="100%"></pre>
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