SCHEDDU is a standard SAP Structure so does not store data like a database table does. It can be used to define the fields of other actual tables or to process "Scheduling Durations SD/WS" Information within sap ABAP programs. This is done by declaring abap internal tables, work areas or database tables based on this Structure. These can then be used to store and process the required data appropriately. i.e. DATA: wa_SCHEDDU TYPE SCHEDDU.
The SCHEDDU table consists of various fields, each holding specific information or linking keys about Scheduling Durations SD/WS data available in SAP. These include DURAGROSS (Scheduling duration in calendar days), DURANET (Scheduling duration in hours/minutes working time), CALENDARID (Calendar ID), WORKINGHRS (Working time from sales view)... See below for full list along with technical details, documentation, text table, check tables, foreign key relationships, conversion routines, relevant tcodes and example ABAP select code etc. .