BAPI_0050_SELCHGDATE 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 "Selection criteria for changed date" 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_BAPI_0050_SELCHGDATE TYPE BAPI_0050_SELCHGDATE.
The BAPI_0050_SELCHGDATE table consists of various fields, each holding specific information or linking keys about Selection criteria for changed date data available in SAP. These include OPTION (Selection operator OPTION for range tables), LOW (Date on which the object was changed), HIGH (Date on which the object was changed)... 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. .