Re: Ingress to PostgreSQL Migration

On Tue, Jan 9, 2024 at 7:00 AM Rakesh Nashine <nashine(dot)rakesh(at)gmail(dot)com>
wrote:

> Hello Ron,
> Yes DB size is around 1TB , in which probably more then 1k tables and same
> indices persist. others objects such as SP,SF and Triggers are also good in
> numbers . It's not HA solution .
>
>
> On Mon, Jan 8, 2024 at 8:06 PM Ron Johnson <ronljohnsonjr(at)gmail(dot)com>
> wrote:
>
>> On Mon, Jan 8, 2024 at 6:45 AM Rakesh Nashine <nashine(dot)rakesh(at)gmail(dot)com>
>> wrote:
>>
>>> Hello All,
>>> I have been assigned to migrate the ingress database to PostgreSQL
>>> database. Can anyone help me with the tools or the strategy we should
>>> follow to do so?
>>>
>>
>> You've not mentioned how big the source database is, nor how many tables,
>> indices, triggers, stored procedures, stored functions, etc, nor whether
>> the Ingres instance uses any High Availability features.
>>
>
>
Converting the triggers and stored procedures/functions will be the biggest
hurdle. The CREATE TABLE and CREATE INDEX statements will probably have
minor syntax differences that "sed" might be able to fix. (Presumably
Ingres has a feature to dump the database's schema into a set of CREATE
TABLE, CREATE INDEX, CREATE ... statements?)

CSV is of course the lowest common denominator for file transfer, and you
want to create everything *except* the plain tables *after* loading the
data into PG tables. And don't forget parallelism when unloading and
loading data.