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There is one sql But I don't know how to solve the problem , I hope someone can help me answer

The problem is ：
Create a test table and corresponding view to check when you can insert . Cover the following ： (1) The view does not contain non default NOT NULL And standard value ; (2) The view does not contain the entire primary key; (3) The view is based on... That spans two tables JOIN Inquire about ; (iv) The view contains a GROUP BY request

among 2 I don't know how to do it

Thank you first

IF OBJECT_ID(N'Abt')is NULL
CREATE TABLE Abt (ANr int PRIMARY KEY, AbtName VARCHAR(20));

IF OBJECT_ID(N'Pers')is NULL
CREATE TABLE Pers (PNr int PRIMARY KEY, PName VARCHAR(40),AbtNrFK int);

ALTER TABLE Pers WITH CHECK ADD FOREIGN KEY(AbtNrFK)
REFERENCES Abt (ANr);

DELETE FROM Abt;

INSERT INTO Abt VALUES (1,'Einkauf');
INSERT INTO Abt VALUES (2,'Verkauf');
INSERT INTO Abt VALUES (3,'Vertrieb');
INSERT INTO Abt VALUES (4,NULL);

DELETE FROM Pers;

INSERT INTO Pers VALUES (1,'Mike Gent',3);
INSERT INTO Pers VALUES (2,'Alex Müller',2);
INSERT INTO Pers VALUES (3,'Leo Bauer',1);
INSERT INTO Pers VALUES (4,'Lena Bauer',2);
INSERT INTO Pers VALUES (5,'SARA Black',4);
INSERT INTO Pers VALUES (6,'David Simon',NULL);
INSERT INTO Pers VALUES (NULL,'Sam Schwarz',3);

CREATE VIEW TEST AS
SELECT PNr,PName,ANr,AbtName
FROM Pers join Abt on ANr=AbtNrFK
GROUP BY PNr,PName,AbtName;