Converting Query from MS SQL

Dear Friends,

I am working with Postgres 7.3.4 on RH Linux 7.2. While migrating all the SPs (from MS SQL Server), I come across these lines in MS SQL Server procedure.

SET @v_sql = "UPDATE "Schema1".employee SET rec_deleted_flag = 'Y' WHERE empid IN (" + @p_list_ids + ");"
EXEC(@v_sql)

Actually to dynamically pass the values for the 'IN' the pass the @p_list_ids (a comma separated string ) to the variable @v_sql and then execute it.

How can I change it for postgres?

Thank you very much for ur support

Regards
Kumar