Sql 错误：表“”的子句条目中缺少；已提取“U行”；

我对SQL非常陌生，所以下面是我尝试运行的查询

WITH fetched_row AS (SELECT * FROM sdmk_stereo_unfiltered_road_feature LIMIT 1)


        UPDATE sdmk_stereo_unfiltered_road_feature
                SET is_processed=true
        FROM (SELECT * FROM sdmk_stereo_unfiltered_road_feature WHERE (st_dwithin(location_modeled, fetched_row.location_modeled, 20, TRUE) AND
                sign_type=fetched_row.sign_type AND
                ts!=fetched_row.ts) ) as candidate_signs
        WHERE candidate_signs.id = sdmk_stereo_unfiltered_road_feature.id;

我也试过了

WITH fetched_row AS (SELECT * FROM sdmk_stereo_unfiltered_road_feature WHERE (is_processed=false OR is_processed=NULL) LIMIT 1),
             candidate_signs AS (SELECT * FROM sdmk_stereo_unfiltered_road_feature WHERE (st_dwithin(location_modeled, fetched_row.location_modeled, 20, TRUE) AND
                sign_type=fetched_row.sign_type AND
                ts!=fetched_row.ts))
        UPDATE sdmk_stereo_unfiltered_road_feature
                SET is_processed=true
        FROM candidate_signs
        WHERE candidate_signs.id = sdmk_stereo_unfiltered_road_feature.id;

但我还是得到了错误

[42P01] ERROR: missing FROM-clause entry for table "fetched_row" Position: 272

我明白，这个错误可能就在这里的某个地方

SELECT * FROM sdmk_stereo_unfiltered_road_feature WHERE (st_dwithin(location_modeled, fetched_row.location_modeled, 20, TRUE) AND
                sign_type=fetched_row.sign_type AND
                ts!=fetched_row.ts)

---

但在调试和使其工作方面仍然没有运气。我想我遗漏了一件很明显的事情。

您不是在调用

中的
获取行中的
：

SELECT * 
FROM sdmk_stereo_unfiltered_road_feature,
     fetched_row
WHERE (st_dwithin(location_modeled, fetched_row.location_modeled, 20, TRUE) AND
                sign_type=fetched_row.sign_type AND
                ts!=fetched_row.ts)

在距离条件下进行连接是有意义的（结果相同，但更清晰）：

请解释你想做什么。样本数据和期望的结果确实有帮助。非函数查询通常不是很有用。解决了所有问题。正如我所说，这应该是很明显的，谢谢你指出：）
SELECT * 
FROM sdmk_stereo_unfiltered_road_feature
 JOIN fetched_row ON st_dwithin(location_modeled, fetched_row.location_modeled, 20, TRUE)
WHERE  sign_type=fetched_row.sign_type 
  AND ts!=fetched_row.ts