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Message-ID: <abf2c0f7-777a-4640-bdac-03d45119e033@aklaver.com>
Date: Wed, 20 Aug 2025 10:56:49 -0700
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Subject: Re: MS SQL to Postgres
To: KK CHN <kkchn.in@gmail.com>, pgsql-general@lists.postgresql.org
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 8/20/25 10:25, KK CHN wrote:
> Hi,
> 
> I am in search of the best practices to migrate from an MS SQL database 
> server to PostgreSQL 16
> 
> Existing DB server MSSQL with 6 Million records and 3.5 TB  with 424 
> Tables running from 2019 onwards.
> 
> Each table has 5 to 16 columns ( basically text, numbers, lat long 
> coordinates , time stamps, and images/voice file (stored in archive 
> folders)reference links, etc.  ).
> 
> I am in need to port / migrate all this data from this MS SQL server to 
> Postgres16 .
> 

Up front, I have not moved data from MSSQL to Postgres. What follows 
will be generic.

> 1. What are the best methods and practices folks employ to do this kind 
> of data porting operations?

Planning and patience.

It is a matter of drawing a map/diagram of where you are now(MSSQL) and 
where you want to end up(Postgres) with steps to get from A to B.

> 2. what are the tools and techniques to explored / employed for this

One that I know of:
	https://pgloader.io/

> 3. How much time is consumed by employing the right tools, the entire 
> porting of 6 million records of 3.5 TB size to Postgres 16 takes

Unknowable at this point. I will say it depends on how many MSSQL 
specific features you use and whether there are Postgres direct 
equivalents or you whether you will need to do extensive modifications.

> 4. Any hurdles or challenges or risks

Changing database vendors.

> 
> Kindly enlighten me with the best practices and  reference materials / 
> links or tutorials to perform these operations successfully.
> 
> Thank you,
> Krishane
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com