📄 otl4_stream_read_iterator.htm
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<h1>OTL 4.0, OTL stream read iterator<br>
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<h1>
OTL stream read iterator<br>
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This template class extends the OTL stream interface with more
JDBC-like, conventional <span style="font-style: italic;">getter</span>
functions. <br>
<pre><font size="+2">template<typename OTLStream, <br> typename OTLException<br></font>#if !defined(<a
href="otl3_compile.htm#OTL_ORA7">OTL_ORA7</a>) <br> // when any flavor of OTL but OTL_ORA7 is defined:<br> // OTL_ORA8, OTL_ORA8I, OTL_ORA9I, OTL_ORA10G,<br> // OTL_ORA10G_R2, OTL_ODBC, OTL_DB2_CLI<br><font
size="+2"> ,typename OTLLobStream<br></font>#endif<br><font
size="+2"> ><br>class otl_stream_read_iterator{<br>public:</font></pre>
<pre> otl_stream_read_iterator(); // default constructor<br> ~otl_stream_read_iterator(); // destructor<br><br> otl_stream_read_iterator(OTLStream& s); <br> // general-purpose constructor, attaches to <a
href="otl3_stream_class.htm">otl_stream</a> s<br> <a
name="attach"></a>void attach(OTLStream& s); // attaches to <a
href="otl3_stream_class.htm">otl_stream</a> s<br> <a name="detach"></a>void detach(void); // detaches from the otl_stream<br> <br> <a
name="next_row"></a>bool next_row(void); <br> // reads the next row, returns true if the row was successfully fetched, <br> // false on the end-of-fetch-sequence.<br><br> <a
name="describe"></a>const <a href="otl3_stream_class.htm#otl_var_desc">otl_var_desc</a>* describe(int& var_desc_len); <br> // describes the output structure of the attached <a
href="otl3_stream_class.htm">otl_</a><a href="otl3_stream_class.htm">stream</a>.<br> // var_desc_len is the total number of elements<br> // in the output structure of the attached otl_stream.<br> // The same information can be obtained via <br> // otl_stream::<a
href="otl3_stream_class.htm#describe_out_vars">describe_out_vars</a>(), which<br> // this object is attached to.<br> <br> // JDBC-like <span
style="font-style: italic;">getter</span> functions.<br> // pos is 1,2,... as in JDBC getXXX functions<br> void get(const int pos, char& c); // gets a char<br> void get(const int pos, unsigned char& c); // gets an unsigned char<br> void get(const int pos, char* s); // gets a null terminated char string<br> void get(const int pos, unsigned char* s); // gets a null terminated unsigned char string<br> void get(const int pos, int& n); // gets a signed 32-bit int<br> void get(const int pos, unsigned int& n); // gets a unsigned 32-bit int<br> void get(const int pos, short int& n); // gets a signed 16-bit int<br> void get(const int pos, long int& n); // gets a signed long 32-bit int <br> void get(const int pos, float& n); // gets a 4-byte floating point<br> void get(const int pos, double& n); // gets an 8-byte floating point<br> void get(const int pos, <a
href="otl3_compile.htm#OTL_BIGINT">OTL_BIGINT</a>& n); // gets a signed 64-bit int<br> void get(const int pos, OTL_STRING_CONTAINER& s); <br> // gets an std::string if #define <a
href="otl3_compile.htm#OTL_STL">OTL_STL</a> is enabled.<br> // gets an std::string if #define <a
href="otl3_compile.htm#OTL_STLPORT">OTL_STLPORT</a> is enabled.<br> // gets an ACE_TString if #define <a
href="otl3_compile.htm#OTL_ACE">OTL_ACE</a> is enabled.<br> // VARCHAR, CHAR, LONG, TEXT, and CLOB values can be read by this function. <br> // gets a <a
href="otl3_compile.htm#OTL_USER_DEFINED_STRING_CLASS_ON">USER_DEFINED_STRING_CLASS</a> instance if #define<br> // <a
href="otl3_compile.htm#OTL_USER_DEFINED_STRING_CLASS_ON">OTL_USER_DEFINED_STRING_CLASS_ON</a> is enabled.<br><br> void get(const int pos, <a
href="otl3_long_string.htm">otl_long_string</a>& s); // gets an otl_long_string<br> void get(const int pos, <a
href="otl3_long_string.htm">otl_long_string</a>*& s); <br> // gets a pointer to otl_long_string. This is more optimal than the previous<br> // function, especially in the case of a large string.<br><br>#if !defined(<a
href="otl3_compile.htm#OTL_ORA7">OTL_ORA7</a>) <br> // when any flavor of OTL but OTL_ORA7 is defined:<br> // OTL_ORA8, OTL_ORA8I, OTL_ORA9I, OTL_ORA10G,<br> // OTL_ORA10G_R2, OTL_ODBC, OTL_DB2_CLI<br><br> <a
name="get_lob_stream_ptr"></a>void get(const int pos, <a
href="otl3_lob_stream.htm">otl_lob_stream</a>*& s); <br> // gets a pointer to otl_lob_stream. This function can be used if the otl_stream<br> // that the read iterator is attached to is in the <a
href="otl3_stream_class.htm#set_lob_stream_mode">LOB stream mode</a>.<br><br>#endif<br><br> void get(const int pos, <a
href="otl3_stream_class.htm#otl_datetime">otl_datetime</a>& s); // gets an otl_datetime<br><br> <a
name="is_null"></a>bool is_null(const int pos); <br> // returns true if the value at position "pos" is NULL. <br> // Otherwise, returns false.<br><br>#if defined(<a
href="otl3_compile.htm#OTL_STL">OTL_STL</a>) || defined(<a
href="otl3_compile.htm#OTL_STLPORT">OTL_STLPORT</a>) || defined(<a
href="otl3_compile.htm#OTL_ACE">OTL_ACE</a>)<br><br><a
name="get_by_name"></a>// The following functions are available <br>// only when #define <a
href="otl3_compile.htm#OTL_STL">OTL_STL</a> or <a
href="otl3_compile.htm#OTL_STLPORT">OTL_STLPORT</a> or <a
href="otl3_compile.htm#OTL_ACE">OTL_ACE</a> is enabled.<br><br><a
name="get_by_name_functions"></a>// JDBC-like <span
style="font-style: italic;">getter</span> (by name) functions.<br> // var_name is a variable / column name from the list that can be retrieved by a call<br> // to the <a
href="#describe">describe</a>() function of this class. All variable names are case insensitive.<br> void get(const char* var_name, char& c); // gets a char<br> void get(const char* var_name, unsigned char& c); // gets an unsigned char<br> void get(const char* var_name, char* s); // gets a null terminated char string<br> void get(const char* var_name, unsigned char* s); // gets a null terminated unsigned char string<br> void get(const char* var_name, int& n); // gets a signed 32-bit int<br> void get(const char* var_name, unsigned int& n); // gets a unsigned 32-bit int<br> void get(const char* var_name, short int& n); // gets a signed 16-bit int<br> void get(const char* var_name, long int& n); // gets a signed long 32-bit int <br> void get(const char* var_name, float& n); // gets a 4-byte floating point<br> void get(const char* var_name, double& n); // gets an 8-byte floating point<br> void get(const char* var_name, <a
href="otl3_compile.htm#OTL_BIGINT">OTL_BIGINT</a>& n); // gets a signed 64-bit int<br> void get(const char* var_name, OTL_STRING_CONTAINER& s); <br> // gets an std::string if #define <a
href="otl3_compile.htm#OTL_STL">OTL_STL</a> is enabled.<br> // VARCHAR, CHAR, LONG, TEXT, and CLOB values can be read by this function. <br><br> void get(const char* var_name, <a
href="otl3_long_string.htm">otl_long_string</a>& s); // gets an otl_long_string<br> void get(const char* var_name, <a
href="otl3_long_string.htm">otl_long_string</a>*& s); <br> // gets a pointer to otl_long_string. This is more optimal than the previous<br> // function, especially in the case of a large string.<br><br>#if !defined(<a
href="otl3_compile.htm#OTL_ORA7">OTL_ORA7</a>)<br> // when any flavor of OTL but OTL_ORA7 is defined:<br> // OTL_ORA8, OTL_ORA8I, OTL_ORA9I, OTL_ORA10G,<br> // OTL_ORA10G_R2, OTL_ODBC, OTL_DB2_CLI<br><br> void get(const char* var_name, <a
href="otl3_lob_stream.htm">otl_lob_stream</a>*& s); <br> // gets a pointer to otl_lob_stream. This function can be used if the otl_stream<br> // that the read iterator is attached to is in the <a
href="otl3_stream_class.htm#set_lob_stream_mode">LOB stream mode</a>.<br><br>#endif<br><br> void get(const char* var_name, <a
href="otl3_stream_class.htm#otl_datetime">otl_datetime</a>& s); // gets an otl_datetime<br><br> <a
name="is_null_by_name"></a>bool is_null(const char* pos); <br> // returns true if the value of the "var_name" variable is NULL. <br> // Otherwise, returns false.<br>#endif<br></pre>
<pre><font size="+2">}; // end of otl_stream_read_iterator</font></pre>
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