The error “Column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause” appears when a query uses ...

Who are these scripts for? You need to troubleshoot performance problems with SQL Server, and you need to do it now. You don't have time to track down a bunch of DMVs, figure out Extended Events, ...

A tool which treats CSV and JSON files as SQL tables, performs SQL SELECT queries on them, and stores the result into CSV and JSON files. Many tools and systems can export their data to CSV. Typical ...

Are you at the beginning of your path as a Business Analyst? Are you feeling perplexed about the meaning of “ETL” and the practical use of SQL alongside Power BI? No need to fret — you’re not the only ...

This article was written in collaboration with Bohan Zhang and originally appeared on the OtterTune website. In this article, we’ll dive into MVCC: what it is, how PostgreSQL does it, and why it is ...

Part of the SQL Server 2022 blog series. Cardinality estimation (CE) is a process used by the query optimizer to estimate the number of rows returned by a query or sub-part of a query. These estimates ...

SQL is neither the fastest nor the most elegant way to talk to databases, but it is the best way we have. Here’s why Today, Structured Query Language is the standard means of manipulating and querying ...

In recent years, web technology carried on growing and at same time, the number of internet users increased significantly in number. Today, a Web server is capable of processing millions of requests ...