FND mig can read data from SQL Server?

I don’t think we have an available functionality to direct import from SQL server. However you should be able to utilize “File Migration” or “Excel Migration” types in IFS data migration to achieve this. i.e. You export data from SQL server in to files and then use IFS “File migration” to import them in to IFS database. Or you export SQL server data in to excel and then use IFS “Excel migration” to import them. 

Following documentations explain how you can use “File Migration” and “Excel Migration”. 

https://docs.ifs.com/techdocs/Foundation1/040_administration/260_data_management/050_data_migration/002_migration_types/010_file_migration/default.htm

https://docs.ifs.com/techdocs/Foundation1/040_administration/260_data_management/050_data_migration/002_migration_types/030_excel_migration/default.htm

You can easily find manual and automated ways which you can use to export data from SQL server database. 

Hope this helps. 

Don Burleson’s website is second-to-none, but he didn’t spell out how to build the init file. His instructions were also for hsodbc in Oracle 10, and dg4odbc is now what you want in 12. Here are my notes on how to do this, with our sensitive bits replaced of course:

On Oracle database server host:
   Create ODBC connection
      64-bit
      System DSN
      Type: SQL Server
      Name: MY_SQL_SERVER_ODBC
      Description: My Thing
      Server: sql.example.com
      "With SQL Server Authentication"
      "Connect to SQL Server to obtain default settings for the additional configuration options"
      User: sqluser
      Password:
      Next screen:
         Don't change the default database.
         Don't attach database filename.
         Use ANSI quoted identifiers.
         Use ANSI nulls, paddings, and warnings.
      Next screen: Just one thing checked.
         Perform translation of character data
   Add entry to listener.ora.
       (SID_DESC =
         (SID_NAME = MY_SQL_SERVER_ODBC)
         (ORACLE_HOME = C:\oracle\product\12.1.0\dbhome_1)
         (PROGRAM = dg4odbc)
       )
   Add entry to tnsnames.ora
      MY_SQL_SERVER_ODBC =
        (DESCRIPTION =
          (ADDRESS = (PROTOCOL = TCP)(HOST =localhost)(PORT = 1521))
          (CONNECT_DATA =(SID=MY_SQL_SERVER_ODBC))
          (HS=OK)
          )
        )
   Add file: C:\oracle\product\12.1.0\dbhome_1\hs\admin\initMY_SQL_SERVER_ODBC.ora
      HS_FDS_CONNECT_INFO = MY_SQL_SERVER_ODBC
      HS_FDS_TRACE_LEVEL = OFF
      HS_FDS_FETCH_ROWS = 1

   Restart listener. (You may need to kill DG4ODBC.EXE from Task Manager if it's running.)
      SET ORACLE_HOME=C:\oracle\product\12.1.0\dbhome_1
      lsnrctl stop && lsnrctl start