You might have heard “data mart” come up in conversations about analytics or business intelligence and wondered how it’s different from a database or a data warehouse. It’s a fair question, because the terms get muddled a lot. Here’s a clear breakdown.
Column-Level Security Explained
You may be aware of a concept called row-level security, which controls which rows a user can see in a table. Column-level security is a similar concept, controls which columns are visible. It solves a different problem. Same table, same rows, but some fields in those rows shouldn’t be visible to everyone.
Think about an employees table. A manager might reasonably see a list of all staff and their departments. But salary? National ID numbers? Personal contact details? These should be visible to the manager, but they probably shouldn’t be visible to most other employees, even if they’re querying the same table.
Understanding Row-Level Security (RLS)
Most developers learn about database permissions in broad strokes. You grant a user access to a table, and they can read it. Simple. But what happens when different users should only see some of the rows in that table? That’s where row-level security comes in.
Fix Error 8110 “Cannot add multiple PRIMARY KEY constraints to table” in SQL Server
If you’re getting SQL Server error 8110 that reads “Cannot add multiple PRIMARY KEY constraints to table…” it’s because you’re trying to add more than one primary key to a table. In SQL Server, a table cannot contain more than one primary key.
It’s quite possible you were trying to create a composite primary key, and so you might need to fix your syntax. If that’s the case, read on.
Data Lineage Explained
Data lineage is one of those concepts that sounds more complicated than it is. Once you understand the basic idea, it’s actually pretty intuitive. And it solves a problem that anyone who works with data has run into.
What is a Data Lake?
Data lake is one of those terms that gets thrown around a lot in conversations about data strategy, often alongside data warehouses and data marts. But what actually is a data lake, and how does it fit into the picture? Let’s find out.
JSON_OBJECTAGG() in SQL Server 2025: Build JSON Objects Straight from Your Queries
SQL Server 2025 ships with a handful of genuinely useful additions, and JSON_OBJECTAGG() is one of the better ones. It lets you aggregate rows into a single JSON object (with key-value pairs pulled directly from your data) without any string hacking or FOR JSON PATH gymnastics.
Here’s what it does, how it works, and when you might actually use it.
What Is ELT?
Data doesn’t always arrive clean, structured, or ready to use. And anyone who’s worked with data knows that gap between raw information and actionable insight is where a lot of the real work happens. ELT is a modern approach to bridging that gap.
Unlike its older cousin ETL, ELT flips the script by loading data into its destination first and transforming it there, taking advantage of the processing power that today’s cloud data warehouses have in abundance. The result is a faster, more flexible pipeline that’s become something of a default choice for many data teams building on platforms like Snowflake, BigQuery, or Redshift.
Fix Error 13680 “Column on table is not of JSON data type” in SQL Server
If you’re getting SQL Server error 13680 that reads something like “Column ‘details’ on table ‘table_name’ is not of JSON data type, which is required to create a JSON index on it.” it looks like you’re trying to create a JSON index on a non-JSON column. You can only create JSON indexes on columns defined with the JSON type.
To fix this issue, be sure that the column is of JSON type before running CREATE JSON INDEX on it.
What is ETL?
If you’ve spent any time around data teams or analytics tools, you’ve probably heard the term ETL thrown around. It sounds technical, but the concept is actually pretty straightforward. This article looks at what the term actually means, how it works, and why it matters.