Eating An Elephant – How To Work With Huge Datasets In Oracle And SQL Server

Simplifying complex problems is difficult but when done, the rewards are definitely worth it. How I single-handedly managed to migrate 55 Billion rows in 4000+ tables: Last year, I created PowerPump a PowerShell based data copy server which continuously migrated 4000+ Oracle tables to SQL Server. It was no simple task given that I had … Continue reading Eating An Elephant – How To Work With Huge Datasets In Oracle And SQL Server

SQL Server: MERGE (AKA UPSERT) =(INSERT / UPDATE / DELETE) – All In One

MERGE statement does INSERT/UPDATE/DELETE For the longest time Oracle and SQL Server users have written code like this (pseudo code) This is great but this is such a common construct that everyone has also been long craving for built in support in the database for what people commonly call UPSERT (UPDATE if key exists else INSERT). … Continue reading SQL Server: MERGE (AKA UPSERT) =(INSERT / UPDATE / DELETE) – All In One

Oracle Tip – COPY Command – When You Don’t Have DataPump

This is an old post that I am re-cycling. The recommended method to copy data around is by using DataPump. However, if you are on an older version of Oracle, COPY command is an easy way to copy data from one database to another or even within the same database. There are countless situations where … Continue reading Oracle Tip – COPY Command – When You Don’t Have DataPump

Oracle REDO – A Basic Explanation

In an earlier post, we saw how Oracle’s UNDO works in very basic terms. REDO is another critical aspect that goes hand in hand with UNDO. Let us get the basics of REDO sorted out here. UNDO and REDO In its most basic sense UNDO is information saved to get back in case a ROLLBACK … Continue reading Oracle REDO – A Basic Explanation

Oracle – Find A Needle In The Hay Stack – How To Pinpoint Data Errors Like “ORA-12899: value too large for column”

Nasty data-related errors: If you are looking to resolve one of these types of errors, you are in the right place. Please keep reading. ORA-01400: cannot insert NULL into (string) ORA-01401: inserted value too large for column ORA-02290: check constraint (string.string) violated ORA-02291: integrity constraint (string.string) violated - parent key not found ORA-02292: integrity constraint … Continue reading Oracle – Find A Needle In The Hay Stack – How To Pinpoint Data Errors Like “ORA-12899: value too large for column”