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When migrate a database from SQL Server to PostgreSQL one of the steps is conversion of views into the destination format. This whitepaper discovers basic rules of this conversion.

1. SELECT ... OFFSET X LIMIT Y is converted into

   SELECT ... OFFSET X ROWS FETCH NEXT Y ROWS ONLY;
   

2. PostgreSQL built-in function POSITION must be reiplaced by MS SQL equivalent CHARINDEX
3. PostgreSQL expression $date + $interval must be converted into SQL Server function call DATEADD($interval, $n_units, $date) according to the table below:

   PostgreSQL Interval	SQL Server Equivalent
   ($date + $n_units * interval '1 day')::date	DAY/DD/D
   ($date + $n_units * interval '1 hour')::date	HOUR/HH
   ($date + $n_units * interval '1 minute')::date	MINUTE/MI/N
   ($date + $n_units * interval '1 month')::date	MONTH/MM/M
   ($date + $n_units * interval '1 second')::date	SECOND/SS/S
   ($date + $n_units * interval '1 week')::date	WEEK/WW/WK
   ($date + $n_units * interval '1 year')::date	YEAR/YY

4. Every occurrence of DATE_PART must be replaced by DATEPART
5. PostgreSQL function NOW() must be converted into SQL Server GETDATE
6. Every occurrence of COALESCE must be replaced by ISNULL
7. PostgreSQL function REPEAT must be converted into SQL Server equivalent REPLICATE