32c40bbf1d
Converts an existing performance-review prompt into 22 atomic knowledge articles under microsoft/knowledge/performance/, each paired with AL samples under samples/performance/<slug>/ demonstrating the anti-pattern and/or the best practice. The full set seeds the corpus the microsoft/skills/al-performance-review leaf skill matches against and validates the READ knowledge-file format end-to-end. Every article conforms to the READ contract: six required frontmatter fields, Description always present, no fenced code blocks, sample code referenced by repo-relative path. Each article is marked with a blockquote 'Seed article' note so domain stewards can extend or restructure them freely. Articles (ordered by concern area): Database query efficiency - use-findset-with-next (AA0181) - avoid-findfirst-with-next (AA0233) - only-fetch-records-you-use (AA0175) - use-findset-readonly-by-default - use-setloadfields-for-partial-records - use-addloadfields-in-report-layouts - use-calcsums-to-aggregate-filtered-sets (file: use-calcsums-for-flowfield-totals.md) - avoid-calcfields-in-loops - add-sift-keys-for-flowfields (AA0232) - use-isempty-for-existence-checks Filter and key optimization - filter-before-find - set-current-key-to-match-filters Temporary tables and transactions - use-temporary-tables-for-intermediate-data - keep-transaction-scope-short - avoid-user-interaction-in-transactions - avoid-commit-inside-loops Record operations - prefer-get-for-primary-key-lookups - use-insert-false-when-skipping-triggers - prefer-direct-record-over-recordref Strings, codeunits, events - use-strsubstno-for-message-formatting - use-single-instance-codeunits-for-caching - keep-event-subscribers-lightweight samples/README.md documents the sample-folder convention and makes clear the samples are demonstration-only, not derived from BC base application source, with unique object IDs in the 50100-50199 range. Rubber-duck pass caught: a misleading good.al in avoid-calcfields-in-loops (fixed by switching to a hoistable CalcFields scenario), an invalid event subscriber signature in keep-event-subscribers-lightweight (fixed by adding var xRec), normative guidance leaked into the Description of use-findset-readonly-by-default (moved to Anti Pattern), a missing sample pair for keep-transaction-scope-short (added), and muddy FlowField/CalcSums framing (retitled and clarified). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Use temporary tables for intermediate data
Seed article. Converted from an existing performance-review prompt to bootstrap the BCQuality performance corpus. Domain stewards should expand, restructure, and refine as needed.
Description
Temporary tables live in memory, not in SQL. They are the correct primary data structure for intermediate results, working sets, and lookup caches that do not need to outlive the current operation. Using a real persisted table for scratch data incurs database round-trips, transaction scope, and locking for data that has no business being persisted.
Best Practice
Declare the record variable with temporary when the data is scratch. Populate it with Insert(false) to avoid firing triggers. Clear the table explicitly with DeleteAll when the variable's scope is long-lived (a SingleInstance codeunit or a reused session variable) and needs to be reset between uses.
See sample: samples/performance/use-temporary-tables-for-intermediate-data/good.al.
Anti Pattern
Writing intermediate results to a real table, processing them, and deleting them afterwards performs the full cost of INSERT and DELETE operations on data that never needed to be transactional.