SQL Data pull put stress on the system?

[keithkeirstead]

We have a third party service that we use that isn't that great at reporting but everything in the reports is stored into a SQL table. I need to pull all of the data from that table (dating back to 2018) to build out some reports. I've never pulled data directly from an SQL database before, does creating the connection and importing/direct querying the table with Power BI put a lot of stress on the system? I'm not quite sure how many lines there are total, but I would just like to be better informed so I won't cause any unnecessary downtime.

[waltheed]

Hi Keith, 

It's a bit hard to answer when I do not know the exact situation, but apparently yo  do not either. So here's what I should do.

Try to connect to the sql database with a tool like SQL Server Management Studio, Azure Data Studio or something similar for other SQL database systems. Check what tables are there and do a select count(*) to check the number of records for each table. And maybe group it by year or so, so you get some idea of how much data you need.

If it's a special database for reporting, then your query will not harm operations, maybe the reports get a bit slower, but OK. If it is a query on the transactional database that people also use for provcessing transactions, then you may need to find a suitable time slot to do that. But in principle is a database meant for storing and retrieving data, so you need not be too scared. 

When you decide to import stuff in Power BI I recommend to set up incremental updates. Then the first load may involve a big data volume, but the subsequent loads only retrieve the new or changed data, and not everything again. 

When you do this step by step, you should be fine.