postgres upsert的部分更新违反了约束条件
问题描述:
我希望能够在postgres(9.5)中部分地插入部分内容,但似乎在部分upsert未满足所有约束条件时会失败(例如非空约束条件)postgres upsert的部分更新违反了约束条件
这里的场景和错误
CREATE TABLE jobs (
id integer PRIMARY KEY,
employee_name TEXT NOT NULL,
address TEXT NOT NULL,
phone_number TEXT
);
CREATE OR REPLACE FUNCTION upsert_job(job JSONB)
RETURNS VOID AS $$
BEGIN
INSERT INTO jobs AS origin VALUES(
(job->>'id')::INTEGER,
job->>'employee_name'::TEXT,
job->>'address'::TEXT,
job->>'phone_number'::TEXT
) ON CONFLICT (id) DO UPDATE SET
employee_name = COALESCE(EXCLUDED.employee_name, origin.employee_name),
address = COALESCE(EXCLUDED.address, origin.address),
phone_number = COALESCE(EXCLUDED.phone_number, origin.phone_number);
END;
$$ LANGUAGE PLPGSQL SECURITY DEFINER;
--Full insert (OK)
SELECT upsert_job('{"id" : 1, "employee_name" : "AAA", "address" : "City, x street no.y", "phone_number" : "123456789"}'::jsonb);
--Partial update that fulfills constraint (Ok)
SELECT upsert_job('{"id" : 1, "employee_name" : "BBB", "address" : "City, x street no.y"}'::jsonb);
--Partial update that doesn't fulfill constraint (FAILS)
SELECT upsert_job('{"id" : 1, "phone_number" : "12345"}'::jsonb);
--ERROR: null value in column "employee_name" violates not-null constraint
--DETAIL: Failing row contains (1, null, null, 12345).
我怎么到处去接近这个的例子吗?
答
想想另一种方式,如果id不存在,该怎么办?你不能插入一个电话号码,因为它没有名字/地址,但这正是你要求它做的。所以约束变得疯狂,并且失败,因为一个upsert 试图插入第一个,然后在插入失败时更新。但是你的插入没有通过约束检查来查看它是否已经存在。
你可以做什么,而不是如果你想partials是告诉它如何处理违反约束的部分。像这样的东西(这是不完整的,不处理所有部分数据场景):
CREATE OR REPLACE FUNCTION upsert_job(job JSONB)
RETURNS VOID AS $$
BEGIN
IF (job->>'phone_number' IS NOT NULL
AND job->>'employee_name' IS NOT NULL
AND job->>'address' IS NOT NULL) THEN
INSERT INTO jobs AS origin VALUES(
(job->>'id')::INTEGER,
job->>'employee_name'::TEXT,
job->>'address'::TEXT,
job->>'phone_number'::TEXT
) ON CONFLICT (id) DO UPDATE SET
employee_name = COALESCE(EXCLUDED.employee_name, origin.employee_name),
address = COALESCE(EXCLUDED.address, origin.address),
phone_number = COALESCE(EXCLUDED.phone_number, origin.phone_number);
ELSIF (job->>'phone_number' IS NOT NULL AND (job->>'employee_name' IS NULL AND job->>'address' IS NULL)) THEN
UPDATE jobs SET phone_number=job->>'phone_number'::TEXT
WHERE id=(job->>'id')::INTEGER;
END IF;
END;
$$ LANGUAGE PLPGSQL SECURITY DEFINER;
我不立即看到这里有什么问题。我建议发布到pgsql-general邮件列表以获得更多的目光。这可能是一个错误。如果你确实写信给邮件列表,*请*在你的邮件列表消息中加入这篇文章的链接。 –