Files
document-haness/docs/clean-architecture-backend-template/tech-log-studio/query-and-pagination-models/concept/concept-adapter-outbound-persistence-jpa-c29.md
T
DongHyeonkaandClaude Opus 5 b2963105a8 docs(keycloak-session-store): import the session-storage lab as a new project
The keycloak project ended with four open questions that design could not
settle. A two-VM lab was built to answer them by measurement, and this is
that material: 26 experiments, 125 raw command outputs, 22 browser captures.

Follows the import procedure in README.md.

  source/     the originating repository verbatim — 78 documents, 28 SVGs,
              8 manifests, plus .source-revision recording the commit
  final/      the SSOT
    document.md   729 lines written from the 29 experiment documents, not
                  concatenated: what was predicted, what was measured, and
                  where the measurement itself was wrong
    evidence/raw    125 outputs, flattened to <experiment>__<file> because
                    the originals collided (01-baseline.txt appeared three
                    times) and the audit only globs the top level
    evidence/meta   one per raw file; command and exitCode are null and the
                    README says why rather than inventing them
    evidence/browser  22 captures
    assets/       three diagrams through techviz
    .techviz/     their VizSpecs

A separate project rather than an addition to keycloak: the B-layer answers
that project's four questions, but the A, C and D layers are about cluster
failure, SSO and operations, and one document.md should hold one subject.
The four question records there can point here through 관계.

Recorded rather than papered over: only three of the 28 diagrams were
remade. The repository forbids hand-drawn SVG and forbids titles inside the
canvas; all 28 originals carry both, so converting them is redrawing, not
reformatting. They stay in source/ and the gap is written into the document.

verify-pipeline.py passes. audit-records.py reports no issues.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-04 22:51:59 +09:00

2.1 KiB

kind, slug, title, topic, project, status, sourceRevision, rootTreeNode, evidenceCapturedOn, assets, evidence, source, module
kind slug title topic project status sourceRevision rootTreeNode evidenceCapturedOn assets evidence source module
CONCEPT adapter-outbound-persistence-jpa-c29 size + 1로 hasNext를 판정하고 COUNT를 없앤다 query-and-pagination-models clean-architecture-backend-template 게시 전 21234e38cdb9a926cbc92bb97a2aee2e4a7d2916 concept:adapter-outbound-persistence-jpa-c29 2026-09-01
key file
adapter-outbound-persistence-jpa-c29 ../../../final/evidence/rendered/adapter-outbound-persistence-jpa-c29.svg
../../../final/evidence/raw/adapter-outbound-persistence-jpa-c29.txt
원본 분석 절은 analysis/05-adapter-outbound-persistence-jpa.md#L1973 이다.
adapter-outbound-persistence-jpa

size + 1로 hasNext를 판정하고 COUNT를 없앤다

JpaKeysetQuerySupportsize + 1을 가져와 최대 size개를 반환하고 추가 1개로 hasNext를 판단한다. 이 path에는 COUNT(*)가 없다.

본문

JpaKeysetQuerySupport의 실행 형태는 이렇다.

query.setMaxResults(page.fetchSize())  // size + 1
 -> result
 -> KeysetSliceAssembler

반환은 최대 size개이고 추가 1개로 hasNext를 판단한다. 이 path에는 COUNT(*)가 없다.

JpaKeysetQuerySupport 참조 위치

:::evidence key="adapter-outbound-persistence-jpa-c29" alt="코드베이스에서 JpaKeysetQuerySupport 를 검색한 출력 6줄. 이 기록이 세는 참조가 그 출력에 그대로 보인다." caption="JpaKeysetQuerySupport 코드베이스 검색 — 6줄 · exit 0" zoom="true" :::

COUNT를 다시 붙이지 않는 이유

keyset을 도입해 OFFSET full-walk 비용을 줄여 놓고 total count로 다시 full-work를 추가하는 구조를 피한다.

별도 레인에서만 확인한 것

실제 PostgreSQL readiness query도 (occurred_at,id) > (?,?) ORDER BY ... LIMIT ? 형태와 representative index 사용을 별도 integration lane에서 검증한다. 해당 entire integration lane 자체는 later sub-scope 11의 denominator이므로 여기서는 cross-scope evidence로만 사용한다.