Effort for Vendor Neutral (MS-SQL- MySQL)

[Mahesh Dilhan]

To : internals@stripped

Currently i'm carrying-out analysis on following basic queries, so that 
i can execute them in MySQL
Scenario – 01 – limit / top
SELECT top 10 * FROM 'table_name'

    MySQL – does not work
    SQL Server - works fine

Scenario – 02 – IFNULL / ISNULL
Select ISNULL(coulmn_name,' ') as new_alias from 'table_name'

    MySQL – does not work
    SQL Server - works fine

i would like to know under-laying implementation of

    MySQL - LIMIT
    MySQL - IFNULL

It would be much helpful to internals@stripped, so that i can 
continue with my analysis

Thank You

Mahesh