如何在 SQL 表中插入默认值？

我有一张这样的桌子:

create table1 (field1 int,
field2 int default 5557,
field3 int default 1337,
field4 int default 1337)

我想插入一行，其中包含 field2和 field4的默认值。

我试过 insert into table1 values (5,null,10,null)，但它不工作，ISNULL(field2,default)也不工作。

如何告诉数据库在插入行时使用列的默认值？

220626 次浏览
小开

Try it like this

INSERT INTO table1 (field1, field3) VALUES (5,10)

Then field2 and field4 should have default values.

小开

If your columns should not contain NULL values, you need to define the columns as NOT NULL as well, otherwise the passed in NULL will be used instead of the default and not produce an error.

If you don't pass in any value to these fields (which requires you to specify the fields that you do want to use), the defaults will be used:

INSERT INTO
table1 (field1, field3)
VALUES   (5,10)
小开
最佳答案

Just don't include the columns that you want to use the default value for in your insert statement. For instance:

INSERT INTO table1 (field1, field3) VALUES (5, 10);

...will take the default values for field2 and field4, and assign 5 to field1 and 10 to field3.

小开

To insert the default values you should omit them something like this :

Insert into Table (Field2) values(5)

All other fields will have null or their default values if it has defined.

小开

Best practice it to list your columns so you're independent of table changes (new column or column order etc)

insert into table1 (field1, field3)  values (5,10)

However, if you don't want to do this, use the DEFAULT keyword

insert into table1 values (5, DEFAULT, 10, DEFAULT)
小开 
CREATE PROC SP_EMPLOYEE                             --By Using TYPE parameter and CASE  in Stored procedure
(@TYPE INT)
AS
BEGIN
IF @TYPE=1
BEGIN
SELECT DESIGID,DESIGNAME FROM GP_DESIGNATION
END
IF @TYPE=2
BEGIN
SELECT ID,NAME,DESIGNAME,
case D.ISACTIVE when 'Y' then 'ISACTIVE' when 'N' then 'INACTIVE' else 'not' end as ACTIVE
FROM GP_EMPLOYEEDETAILS ED
JOIN  GP_DESIGNATION D ON ED.DESIGNATION=D.DESIGID
END
END
小开

This works if all the columns have associated defaults and one does not want to specify the column names:

insert into your_table
default values
小开

You can write in this way

GO
ALTER TABLE Table_name  ADD
column_name decimal(18, 2) NOT NULL CONSTRAINT Constant_name DEFAULT 0
GO
ALTER TABLE Table_name SET (LOCK_ESCALATION = TABLE)
GO
COMMIT
小开 
CREATE TABLE #dum (id int identity(1,1) primary key, def int NOT NULL default(5), name varchar(25))


-- this works
INSERT #dum (def, name) VALUES (DEFAULT, 'jeff')


SELECT * FROM #dum;


DECLARE @some int


-- this *doesn't* work and I think it should
INSERT #dum (def, name)
VALUES (ISNULL(@some, DEFAULT), 'george')


SELECT * FROM #dum;
小开

I had a case where I had a very simple table, and I basically just wanted an extra row with just the default values. Not sure if there is a prettier way of doing it, but here's one way:

This sets every column in the new row to its default value:

INSERT INTO your_table VALUES ()

Note: This is extra useful for MySQL where INSERT INTO your_table DEFAULT VALUES does not work.


提交答案