CMS_STR_PCN_PLMSG 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 "Messages for a plausibility" 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_CMS_STR_PCN_PLMSG TYPE CMS_STR_PCN_PLMSG.
The CMS_STR_PCN_PLMSG table consists of various fields, each holding specific information or linking keys about Messages for a plausibility data available in SAP. These include MSG_TYPE (Message Type), PROC_OBJ (Process Object), PL_CHECKID (Plausibility Check), MSG_CLASS (Application Area)... 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. .