XQuery Comparisons use different rules for general sequence operators and singleton value operators. I make equality and inequality visible side by side. A general unequal-pair result is not always the inverse of an equal-pair result.
SQL – Biggest Concerns in a Data Driven World
The snooping debate made users distrust how their data is used. Here are the biggest concerns for companies taking a data driven approach to business.
Real-Time Operational Analytics With a Filtered Columnstore Index
Build real-time operational analytics with a filtered columnstore index, inspect batch-mode plans and rowgroups, and measure write costs.
Measuring Space Used by Tables per Filegroup in T-SQL
Measure tables per filegroup from allocation metadata, include LOB and overflow pages, and separate partition placement from growth history.
Finding the Most Frequent Value per Group in T-SQL
Find the most frequent value in each group, choose a tie policy, and compare categorical modes with averages and numeric percentiles.
A WHERE Filter That Turns Your LEFT JOIN Into an INNER JOIN
Fix a LEFT JOIN whose right-table WHERE filter removes unmatched rows, inspect the inner-join plan, and search modules for candidates.
The PRODUCT Aggregate: Multiplying Values Across Rows
Use the PRODUCT aggregate in SQL Server 2025 for growth factors and independent probabilities, with checks for NULL, zero, and precision.