我希望能够在 postgres (9.5) 中进行部分更新插入,但是当并非所有约束都得到满足时(例如非空约束),部分更新插入似乎会失败
这是场景和错误的示例
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).
我该如何解决这个问题?
最佳答案
换个角度想,如果id不存在怎么办?您不能只插入一个电话号码,因为它没有姓名/地址,但这正是您告诉它要做的。所以约束变得疯狂并且它失败了,因为更新插入首先尝试插入然后在插入失败时更新。但是您的插入没有通过约束检查以查看它是否已经存在。
如果你想要部分,你可以做的是告诉它如何处理违反约束的部分。像这样的东西(这不完整并且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;
关于postgresql - postgres upsert 的部分更新违反了约束,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/40669555/