Monthly Archives: September 2017

T-SQL Window functions syntax

Window functions are an advanced and powerful feature of the T-SQL language. I will give a few tips on how to use and examples on the AdventureWorks2014 OLTP database. Here I will give some notes on how to use them: … Continue reading

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How to use Windows on a Macbook Pro with 128GB of storage

In this post I will explain my laptop setup which I consider quite practical. This is a quick highlight of my setup: 128GB 13″ Retina Macbook Pro Windows 10 on a special Bootcamp partition Parallels Desktop on MacOs to run Windows … Continue reading

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Advanced data analysis for cBioPortal

As part of my application for the cBioPortal Google Summer of Code position I made this Jupyter notebook in which I demonstrated how different studies (RDBMS equivalent of a table) could be clustered together into types of studies based on the attributes … Continue reading

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Advanced T-SQL: Best way to find the last 3 orders a customer made

INTRODUCTION AND PROBLEM STATEMENT Assuming we have two tables in our database, Customers and orders, our goal is to find the last three orders the customer made. The query should output 3 columns: custid, orderid and orderdate. You can also … Continue reading

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SQL Server Security Basics – Logins and Users

1. Logins and users basics There are two main levels of security in SQL Server. Access to the server Access to a database (* there are also schemas on a database/table level but I will not cover them now) Thus … Continue reading

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