Two SQL Queries to find rows present in one table but not another.

Sometimes when querying SQL tables, you wish to find rows that are missing as opposed to the rows which are present. In this post, I’ll demonstrate 2 queries you can use to determine rows that are present in one table but missing in another table…

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RECURSIVE CTE Fun with SUBSTRING() in MySQL

Although I primarily work with MySQL/MariaDB these days on back-end web development projects, I am studying Oracle SQL with the end goal to become certified. I recently watched a great YouTube video and decided to try my hand porting over the Oracle SQL queries to comparable MySQL for a learning exercise. This blog post details the queries I came up with for the end results. Continue reading for some fun recursive CTE’s using the SUBSTRING() character function and interesting output display variations.

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How to use the NVL and NVL2 functions in Oracle SQL

As an SQL professional or developer, at some point, you’re going to encounter the infamous NULL value (or marker as some say). NULL‘s can be super tricky to get right until you halfway understand them. Fortunately, all the popular SQL vendors have various functions in place that help work with NULLs. In this post, I cover 2 such functions found in the Oracle database, NVL() and NVL2().

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How to Rename an SQL Table

There are a number of reasons why you may need to rename a table in your SQL Database. Whatever the case may be, the process is super-easy. In this post, I share 2 different ways you can rename an existing table in the Oracle Database. Continue reading and learn how…

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Import CSV file with Oracle SQL Developer

If you’re working with Oracle SQL and need to load CSV data into one of your tables, using Oracle SQL Developer makes this process a breeze. Continue reading to see a simple example and learn how…

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