If you're using af:table and row selection is enabled for the table, a must for the table is 'Row Header'. Row header enables the user to select a single row from the table. To add a row header to the table, just add a blank column
as the first column and specify
width="5",
minimumWidth="5" and
rowHeader="true" and specify
align="right". Don't include any field inside this row header column.
Below is the code for row header. You can copy-paste this code as a first column in the table and that's it. You're done!
<af:column id="c4" rowHeader="true" width="5" minimumWidth="5"
align="right"/>
Sample screen shots:
Table without row header:
Table after adding row header: