What Is NoSQL? It is a family of data models other than the classic table, each built for one kind of access pattern. This post covers the four data models, eventual consistency and the CAP theorem in plain words, and how to choose.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
Cohort Retention Tables in T-SQL: From Raw Events to a Grid
Build a retention grid from raw orders with five rows you can check by eye. Includes the DISTINCT rule and why unfinished months show NULL.
Counting Current Connections by Login, Host and Application
Try counting current connections by login, host, application and database, then inspect sleeping transactions and save a baseline.
Big Data Architecture Today: The Lakehouse and Medallion Layers
Big Data Architecture today is a pipeline with four jobs: ingest, store, process and serve, with governance underneath. This post explains the lakehouse, the bronze, silver and gold layers, batch and streaming, and where SQL Server 2025 fits.
Evolution of Big Data: From Flat Files to the Lakehouse
Evolution of Big Data follows one pattern: data grew, the old tool strained, and someone built the next one. This post walks from flat files and the relational model through warehouses and the cloud to the lakehouse.
The 5 Vs of Big Data: Volume, Velocity, Variety, Veracity and Value
The 5 Vs of Big Data are volume, velocity, variety, veracity and value. This post walks a grocery chain through each one, so you can ask the same five questions about your own data before you choose a tool.
Data Lake vs Data Warehouse: What Each One Is For
Data Lake vs Data Warehouse is a choice between raw files and cleaned, modeled tables. This post compares schema on read with schema on write, who uses each, and why many teams combine them in a lakehouse.
SQL Server slow? Let's fix it together in about four hours.
In my Comprehensive Database Performance Health Check, you share your screen, I guide you, and we fix your biggest performance troublemakers. No passwords. No remote access.
You keep every script, and the know-how to fix it yourself next time.
Want your whole team to learn it?
My Practical Workshop has no PowerPoint, just live demos. My AI Enablement Workshop shows your team where AI saves hours, and where it quietly costs them.
Over 400 customers have worked with me this way, and not one shared a password. See all consulting options.
Who We Are
Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 24 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.
Pinal has authored 19 books and 125 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.
Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).
Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.
Shaivi Pinalkumar Dave is a book author and a women’s artistic gymnast.

