Re: Migration from DB2 to PostgreSQL

sachin kotwal wrote:
> While migrating my application from DB2 to PostgreSQL.
>
> I want to migrate following functions in PostgreSQL.
>
> TO_CHAR() in DB2 which can take three arguments as follows:
>
> SELECT TO_CHAR(CURRENT_DATE,'YYYY-MM-DD',112.50) FROM SYSIBM.SYSDUMMY1
>
> I am not sure what is the purpose of third argument in TO_CHAR() function of
> DB2.
>
> I think we can create one user define function with name TO_CHAR which can
> take three argument like DB2.
>
> I want to know that if we want to create user define function TO_CHAR().
> What should be the data type of third argument?
>
> which can handle maximum data types and more suitable for real time
> scenarios.

Look at IBM's documentation at
http://pic.dhe.ibm.com/infocenter/db2luw/v10r1/index.jsp?topic=%2Fcom.ibm.db2.luw.sql.ref.doc%2Fdoc%2Fr0007110.html

TO_CHAR is a synonym for VARCHAR_FORMAT.
The third argument is an optional locale name, like 'en_US',
which will be used to generate the text parts of the
format you chose.

For a format like 'YYYY-MM-DD' this has no effect at all
and can be omitted.

PostgreSQL has no such capability. Unless you need that and
want to code it yourself, the best solution would be to
write a function that just ignores the third argument.

Yours,
Laurenz Albe