Tag
#performance
1 pattern, 3 snippets and 3 experiments.
- Experiment How a Database Index Works: A B-Tree in 3D Watch SQL Server find customers by ID and by surname, page by page. An interactive Three.js model of a table, an index, key lookups and page splits.
- Experiment How SQL Server Joins Tables: Nested Loops, Hash and Merge, Side by Side Watch SQL Server's three join algorithms join the same rows at the same time, then see which one does the least work at real table sizes, and why.
- Experiment How to Read a SQL Server Execution Plan, in 3D An interactive 3D execution plan viewer. See where a query's cost goes, why a scan, a key lookup or a bad estimate slows it down, or paste your own plan.
- Snippet SQL Server: Query Large XML Documents Without Timeouts Why shredding a big XML file with nodes() can take minutes, and the fixes that bring it back to seconds: no parent axis, full paths, text(), shredding once.
- Pattern Changing Large Volumes of Production Data Without an Outage Planning backfills and clean-ups that touch millions of rows while the system stays live.
- Snippet SQL Server: Update or Delete Millions of Rows in Batches Change large volumes of data in small batches to avoid table locks, log growth and blocking.
- Snippet SQL Server: Update Only When Values Change Avoid unnecessary writes and locking by updating rows only when values differ.