Question { IBM, 11865 }

why we use 4 msg variable in BDCMSGCOLL stucture in BDC? why
not more or less than 4?

Answer

Because structure has only 4 fields to fill the messages,
they are just 4 because there are the same number of system
variables that are filled with message data
SY-MSGV1...SY-MSGV4,actually they take the values from the
table "T100" which has 4 place holders which are used to
point the whole message,these values are take by the 4 msg
variables in BDCMSGCOLL and it is also standard structure
which contains only the 4 variables.

Question { IBM, 7955 }

Suppose in an ALV report in grid we have to disply matnr,
ernam,ebeln,ebelp etc.But when we bring the cursor on that
specified field it will show "material number" for matnr,
"purchase Document Number" for ebeln etc. how do you acheive
this?

Answer

To achieve this functionality in fieldcatalog section
activate the field " REPTEXT_DDIC" i.e. REPTEXT_DDIC = 'X'.