public String toString() {
		String sql = "REPLACE "+table;
		
		if(expressions != null && columns != null ) {
			//the SET col1=exp1, col2=exp2 case
			sql += " SET ";
			//each element from expressions match up with a column from columns.
			for (int i = 0, s = columns.size(); i < s; i++) {
				sql += ""+columns.get(i)+"="+expressions.get(i);
				sql += (i<s-1)?", ":"";
			}
		}
		else if( columns != null ) {
			//the REPLACE mytab (col1, col2) [...] case 
			sql += " "+PlainSelect.getStringList(columns, true, true);
		}
		
		if( itemsList != null ) {
			//REPLACE mytab SELECT * FROM mytab2
			//or VALUES ('as', ?, 565)
			
			if( useValues ) {
				sql += " VALUES";
			}
			
			sql += " "+itemsList;
		}
		
		return sql;
	}