Databses

Let’s write our own database!

I think it is a time to do something really crazy, write something which probably doesn’t give any value any of you instead of me, let’s write our own database from scratch! 😀 Until today I know quite good how databases work from a data management perspective. Especially Oracle allows you to study more of processes in data base, because …

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SQL ON conditions in left join

When you use SQL for your daily work, you probably can don’t know that when you use JOIN then where is not the only way to set a condition, but let me explain this for you step by step. 1.Let’s assume that you have 2 tables. Content of first one 2.Content of the second one 3. Now let’s get only …

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How to install DWF on SAP Hana Express

Hello all, Last time, during opens course „Modern Data Warehousing with SAP BW/4HANA”, I learned about SAP SQL Data Warehousing. This topic was even more exciting to me, because I’m an SAP BW Consultant, and I don’t knew before about possibility to build your own SAP Warehouse directly on HANA database. So why I can’t just install this add-on on …

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How oracle saves your tables ?

All of you probably at least once in your life try to insert some records to a database table, but is anyone of you ever try to understand how Oracle actually saves the entries in the database? Last time I was making a small experiment and I want to share my results with you. Step one, let’s build a small …

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