Explain order without ORDER BY through parallel scans, NOLOCK allocation scans, alternate indexes, shared scans, and the explicit sort fix.
Optimized Plan Forcing: Cutting Compile Time in SQL Server 2022
Check optimized plan forcing in SQL Server 2022 through scoped configuration and Query Store replay flags, then compare compile duration.
Table Partitioning Quiz: When Does It Make a Query Faster?
This Table Partitioning Quiz asks whether a query for last month runs faster once a sales table is partitioned by month. The answer is only when the filter lets SQL Server skip partitions. A tested script shows the partition count, the reads, and a partition SWITCH.
Query Store Quiz: Where Is Last Week’s Slow Query?
This Query Store Quiz starts with a slow query from last week and a plan cache that restarted empty. The answer is Query Store, which keeps plans and run times inside the database. A tested T-SQL script finds the query, its plan and its duration.
Stored Procedure Recompile Quiz: What Forces a New Plan?
This Stored Procedure Recompile Quiz asks which action makes SQL Server build a new plan for a procedure. The answer is a new index on a table it reads. A tested script uses plan counters to show what reuses the plan and what rebuilds it.
Scalar Functions and Performance
Scalar functions can hide row-by-row work in SQL Server; learn when inlining helps, how to inspect eligibility, and when a set-based rewrite wins.
Parameter Types From .NET: Stopping Implicit Conversions at the Source
Match parameter types from .NET to SQL Server columns, avoid implicit conversions, and inspect cached plans for mismatched strings.