c++ - how to get day of week from sqlite date and time string? -

i using sqlite datetime commands get, set , manipulate date , time strings. first construct sql command in const char* , execute command using sqlite3_exec while using call function fetch results if (select from) commands.

orderdatabaserc = sqlite3_exec(orderdatabase, psql[i], callback, 0, &zerrmsg); 

now want know day of week (mo-su) , month (jan-dec) date , time string.

how do in sqlite? documentation says can wiser documentation , examples hard find.

let me give examples of sql commands using:

"create table ordertable (orderid integer primary key asc, customerid integer, ordervalue, orderdescription, orderdatetime date, orderduedatetime date)"  "create trigger insert_ordertable_orderdate after insert on ordertable begin update ordertable set orderdatetime = datetime('now') rowid = new.rowid; end;"  "update ordertable set orderduedatetime = datetime('" << iorderdatetime << "', '+1 day') orderid = " << orderid 

so need able know day of week , month of date time string.

according suggestion below have constructed following statement , fired off sqlite3_exec:

"select strftime('%a', orderdatetime) ordertable orderid = " << orderid; 

then in callback function following code (azcolname[i] seems come copy of sql statement:

char* columnname;  for(int i=0; i<argc; i++) {   columnname = azcolname[i];   string dayofweek;    if(strcmp(columnname, "strftime('%a', orderdatetime)")==0)   {     dayofweek = string(argv[i]);   }   ... } 

but crashes on

dayofweek = string(argv[i]); 

use strftime() %w , %m.