Function addTPTParentJoinsForRelation

packages/sql/src/AbstractSqlDriver.ts:2707–2731

* Walks the TPT inheritance chain of `leafMeta` and INNER JOINs each parent table. * Registers the parent aliases in `qb.state.tptAlias` so column resolution finds them * when filter conditions reference parent-table columns. * @internal

(
    qb: AnyQueryBuilder<T>,
    leafMeta: EntityMetadata,
    leafAlias: string,
    basePath: string,
  )

   * @internal
   */
  protected addTPTParentJoinsForRelation<T extends object>(
    qb: AnyQueryBuilder<T>,
    leafMeta: EntityMetadata,
    leafAlias: string,
    basePath: string,
  ): void {
    let childAlias = leafAlias;
    let childMeta: EntityMetadata = leafMeta;

    while (childMeta.tptParent) {
      const parentMeta = childMeta.tptParent;
      const parentAlias = qb.getNextAlias(parentMeta.className);
      qb.createAlias(parentMeta.class, parentAlias);
      qb.state.tptAlias[`${leafAlias}:${parentMeta.className}`] = parentAlias;
      qb.addPropertyJoin(
        childMeta.tptParentProp!,
        childAlias,
        parentAlias,
        JoinType.innerJoin,
        `${basePath}.[tpt]${childMeta.className}`,
      );
      childAlias = parentAlias;
      childMeta = parentMeta;
    }
  }

  /**
   * Adds LEFT JOINs and fields for TPT polymorphic loading when populating a relation to a TPT base class.