Function addFromObject

packages/db/src/query/compiler/select.ts:295–403

* Helper function to process select objects and build operations array

(
  prefixPath: Array<string>,
  obj: any,
  ops: Array<SelectOp>,
)

 * Helper function to process select objects and build operations array
 */
function addFromObject(
  prefixPath: Array<string>,
  obj: any,
  ops: Array<SelectOp>,
) {
  for (const [key, value] of Object.entries(obj)) {
    if (!key.startsWith(`__SPREAD_SENTINEL__`)) {
      assertSafeAliasSegments(key.split(`.`))
    }
    if (key.startsWith(`__SPREAD_SENTINEL__`)) {
      const rest = key.slice(`__SPREAD_SENTINEL__`.length)
      const splitIndex = rest.lastIndexOf(`__`)
      const pathStr = splitIndex >= 0 ? rest.slice(0, splitIndex) : rest
      const isRefExpr =
        value &&
        typeof value === `object` &&
        `type` in (value as any) &&
        (value as any).type === `ref`
      if (pathStr.includes(`.`) || isRefExpr) {
        // Merge into the current destination (prefixPath) from the referenced source path
        const targetPath = [...prefixPath]
        const expr = isRefExpr
          ? (value as BasicExpression)
          : (new PropRef(pathStr.split(`.`)) as BasicExpression)
        const compiled = compileExpression(expr)
        ops.push({ kind: `merge`, targetPath, source: compiled })
      } else {
        // Table-level: pathStr is the alias; merge from namespaced row at the current prefix
        const tableAlias = pathStr
        const targetPath = [...prefixPath]
        ops.push({
          kind: `merge`,
          targetPath,
          source: (row) => (row as any)[tableAlias],
        })
      }
      continue
    }

    const expression = value as any
    if (isConditionalSelectValue(expression)) {
      if (containsAggregate(expression)) {
        ops.push({
          kind: `field`,
          alias: [...prefixPath, key].join(`.`),
          compiled: () => null,
        })
        continue
      }

      ops.push({
        kind: `field`,
        alias: [...prefixPath, key].join(`.`),
        compiled: compileConditionalSelect(expression),
      })
      continue
    }