postgresql - 如何在 ON CONFLICT DO UPDATE SET X = OLD.X + EXCLUDED.X 中引用 OLD.X

Question

在 ON CONFLICT DO UPDATE 中有一个“旧值”的别名？

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我的现实生活问题是

INSERT INTO art.validterm (namespace,term,X,info)
    SELECT namespace,term,array_agg(Xi), 'etc'
    FROM term_raw_Xs
    GROUP BY namespace,term
ON CONFLICT (term) DO 
    UPDATE SET aliases=OLD.X||EXCLUDED.X 
    WHERE term=EXCLUDED.term

PS:问题是不存在“OLD”。解析器说只有 X 是不明确的。

Answer 1

简单地将 OLD 替换为表的名称，在您的情况下:validterm，对我有用。

我的测试:

DROP TABLE IF EXISTS work.term_raw;

CREATE TABLE work.term_raw
(
unique_field INT UNIQUE,
x_field TEXT
);

INSERT INTO work.term_raw VALUES (1, 'A');

INSERT INTO work.term_raw VALUES (1, 'B')
ON CONFLICT (unique_field) DO UPDATE SET x_field = term_raw.x_field || EXCLUDED.x_field;

SELECT * FROM work.term_raw;

我的结果: