# 지원 매트릭스가 이 게이트에 붙인 목적
115:| `collection-fetch-pagination` | gate | a paged collection fetch silently reading the whole table and paginating in memory |

# 테스트가 무엇을 단언한다고 적는가
16:/**
17: * The collection-fetch pagination gate (design §26).
18: *
19: * <p>The failure this exists to catch is in-memory pagination: older providers fetched every
20: * matching parent row and applied the page in Java, logging a warning and returning correct results
21: * while reading the whole table. Correct output, unbounded work, and nothing failing anywhere.
22: *
23: * <p>The assertion is therefore on the <em>generated SQL</em>, not on the returned page size. The
24: * page is identical either way; only the SQL says where the limit was applied.
25: */
26:@Tag("jpa-contract")
27:class HibernateCollectionFetchPaginationContractTest {
28:
29:  private static final int PARENTS = 50;
30:  private static final int CHILDREN_PER_PARENT = 4;
31:  private static final int PAGE_SIZE = 20;

# 그 테스트가 실제로 단언하는 것
3:import static org.assertj.core.api.Assertions.assertThat;
29:  private static final int PARENTS = 50;
30:  private static final int CHILDREN_PER_PARENT = 4;
31:  private static final int PAGE_SIZE = 20;
63:  @DisplayName("a paged collection fetch bounds the parent selection in SQL")
78:    assertThat(page).hasSizeLessThanOrEqualTo(expected.maxReturnedParents());
79:    assertThat(expected.requiresDatabaseLimit()).isTrue();
83:  @DisplayName("the fetched page issues one statement, not one per parent")
97:          page.forEach(parent -> assertThat(parent.children()).isNotNull());
101:    assertThat(delta.preparedStatements())
107:  @DisplayName("without a fetch join the same access is an N+1")
118:          page.forEach(parent -> assertThat(parent.children()).hasSize(CHILDREN_PER_PARENT));
122:    assertThat(delta.collectionFetches())
128:  @DisplayName("row amplification stays inside the declared bound")
141:    assertThat(rows).isLessThanOrEqualTo(expected.maxRowAmplification());

# 두 번째 단언이 보는 값은 어디서 오는가
33:  public static FetchPaginationExpectation hibernate74PostgreSql(int pageSize) {
34:    return new FetchPaginationExpectation(pageSize, true, pageSize * 100);
33:  public static FetchPaginationExpectation hibernate74PostgreSql(int pageSize) {
34-    return new FetchPaginationExpectation(pageSize, true, pageSize * 100);
35-  }

# 같은 리프의 이웃 클래스가 이 형태를 이름으로 부른다
16- *
17- * <p>The alternative — asserting the declared baseline as if it were the runtime one — would give a
18: * green check that proves the constant equals itself while the collection-fetch-pagination gate
19- * runs against a different provider entirely. See {@code docs/jpa/repository-adaptation.md} §4.
20- */