dtl

Example: Using a DynamicDBView to insert records into the database. Illustrates writing NULL values to the database.

// Using a DynamicDBView to insert records into the database.

// this example also shows how to set NULL fields in a variant_row

// Insert two rows into a table with unknown fields
void SimpleDynamicWrite() {
	TIMESTAMP_STRUCT paramDate = {2012, 12, 23, 0, 0, 0, 0}; 
	// Mayan DOOMSDAY! End of the Mayan 5126 year long calendar cycle starting from May 1, 3094 B.C.
	// Date is 13.13.13.0.0.0.0  4 Ahaw, 3 K'ank'in
	
	DynamicDBView<> view("DB_EXAMPLE", "*");

	DynamicDBView<>::insert_iterator write_it = view;

	// NOTE: We need to construct r from the view itself since we
	// don't know what fields the table will contain.
	// We therefore make a call to the DataObj() function to have the
	// table return us a template row with the correct number of fields
	// and field types.
	variant_row r(view.GetDataObj());

	// Prepare the number of the beast!
	// Set all fields to the value 6,
	// except for the last column which is a date and cannot
	// currently accept numeric values
	for (size_t i = 0; i < r.size()-1; i++)
	{
		 r[i] = 6;
	}
	r[i] = paramDate;  // set the Doomsdate

	// insert the number
	*write_it = r;
	write_it++;

	// Prepare the number of angels who stand before
	// the throne of God!
	// Set all fields to the value 7,
	// except for the last column which is a date and cannot
	// currently accept numeric values
	for (i = 0; i < r.size()-1; i++)
	{
		 r[i] = 7;
	}
	r[i] = paramDate;

	// insert the number
	*write_it = r;
	write_it++;

	// Insert Purgatory (the void) into the database.
	// Set all fields to NULL
	for (i = 0; i < r.size()-1; i++)
	{
		 r[i] = NullField();
	}
	r[i] = NullField();

	// insert the number
	*write_it = r;
	write_it++;

	// For more on this example - see the *REAL* DTL homepage!
}

Copyright © 2002, Michael Gradman and Corwin Joy.

Permission to use, copy, modify, distribute and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appears in all copies and that both that copyright notice and this permission notice appear in supporting documentation. Corwin Joy and Michael Gradman make no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty.

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