In this article we explore schema evolution capabilities and limitations in Databricks with regular parquet format and explore schema evolution features and capabilities through delta format with inserts, appends, and overwrites.
Introduction In my last article, An Introduction to Azure Data Explorer, I discussed the process of creating and using Azure Data Explorer. Azure Data Explorer is mainly used for storing and running interactive analytics on Big Data. First, I need to create the ADX cluster. Then, one or more databases should be created inside the […]
The three themes for speakers at this year's PASS Data Community Summit are: Back to Basics, Reach for the Clouds, and Level Up. The goal here is content that covers a wide variety of areas, with many fewer restrictions from previous years. Perhaps the big thing to note for this year's event is: Free. That's […]
In this article we cover what a Common Table Expression CTE is and how to write a CTE for doing selects, inserts, deletes, updates and more.
Director at ThoughtWorks Pramod Sadalage explores trends such as rapid digital transformation and an ever-changing tech landscape, that'll change the way we work with databases and DevOps in the next 20 years.
Tesla is updating their software in a real world, real life DevOps that their customers experience every day. It impresses Steve and tempts him to get one of their cars.
This article examines how to split a data set for training and testing and evaluating our model using Python.
How to create and maintain a 'data dictionary' for your databases, in JSON format, which you can then use to add and update the table descriptions, whenever you build a new version using Flyway.
Using sequences when scaling up with Oracle RAC presents more issues with contention. In this article, Jonathan Lewis explains how to avoid the problems.
It's a holiday weekend in the US this weekend. As such, many of you will be taking a break from work and enjoying time with family, as well as remembering some history in the US. If you're in the rest of the world, hopefully you have a holiday coming up soon you can enjoy. One […]
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Comments posted to this topic are about the item Fun with JSON II
Comments posted to this topic are about the item Changing Data Types
Comments posted to this topic are about the item Answering Questions On Dropped Columns
I have some data in a table:
CREATE TABLE #test_data
(
id INT PRIMARY KEY,
name VARCHAR(100),
birth_date DATE
);
-- Step 2: Insert rows
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT t1.[key] AS row,
t2.*
FROM OPENJSON(
(
SELECT t.* FROM #test_data AS t FOR JSON PATH
)
) t1
CROSS APPLY OPENJSON(t1.value) t2; See possible answers