I am creating a new table in Microsoft SQL server 2000 by writing the code instead of using the GUI, I am trying to learn how to do it "the manual way".
This is the code I am actually using, and it works fine:
CREATE TABLE "attachments"
(
"attachment_id" INT NOT NULL,
"load_date" SMALLDATETIME NOT NULL,
"user" VARCHAR(25) NOT NULL,
"file_name" VARCHAR(50) NOT NULL,
CONSTRAINT "pk_attachments" PRIMARY KEY ("attachment_id"),
CONSTRAINT "fk_users" FOREIGN KEY ("user") REFERENCES "users" ("user"),
CONSTRAINT "ch_load_date" 开发者_开发知识库CHECK ("load_date" < GETDATE())
)
I have specified the primary key, foreign key and check constraints on their own because in this way I can define a name for them, otherwise declaring them inline would make SQL Server generate a random name, and I do not "like" it.
The problem arose when I tried to declare the default value constraint: looking at the informations on the internet and how Microsoft SLQ Server Management Studio creates it, I understood that it can be created both inline and on its own:
"load_date" SMALLDATETIME NOT NULL DEFAULT GETDATE()
or
CONSTRAINT "df_load_date" DEFAULT GETDATE() FOR "load_date"
The inline method works fine, but it generates as usual a random name for the constaint, the stand alone method throws an error, saying Incorrect syntax near 'FOR'.
.
Also, if I create the table and then ALTER
it, the command works:
ALTER TABLE "attachments"
ADD CONSTRAINT "df_load_date" DEFAULT GETDATE() FOR "load_date"
As a reference, here is the full code I am trying to execute:
CREATE TABLE "attachments"
(
"attachment_id" INT NOT NULL,
"load_date" SMALLDATETIME NOT NULL,
"user" VARCHAR(25) NOT NULL,
"file_name" VARCHAR(50) NOT NULL,
CONSTRAINT "pk_attachments" PRIMARY KEY ("attachment_id"),
CONSTRAINT "fk_users" FOREIGN KEY ("user") REFERENCES "users" ("user"),
CONSTRAINT "ch_load_date" CHECK ("load_date" < GETDATE()),
CONSTRAINT "df_load_date" DEFAULT GETDATE() FOR "load_date"
)
I'm totally at loss here, is what I am trying to do not possible, or I am doing something wrong?
Edit:
David M showed how to add a named default constraint using the inline syntax, I am still looking to understand if the stand alone syntax is completely wrong or it is my fault.
Do it inline with the column creation:
[load_date] SMALLDATETIME NOT NULL
CONSTRAINT [df_load_date] DEFAULT GETDATE()
I have used square brackets rather than quotes as many readers won't work with QUOTED_IDENTIFIERS
on by default.
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