MLST_CLEAR 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 "Doc. table fields, which are reset when copied" 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_MLST_CLEAR TYPE MLST_CLEAR.
The MLST_CLEAR table consists of various fields, each holding specific information or linking keys about Doc. table fields, which are reset when copied data available in SAP. These include USERH (Milestone created by), DATEH (Milestone created on), USERV (Milestone changed by), DATEV (Milestone changed on)... 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. .