Most guides on the SQL 'Create Table' command seem to only include the most basic arguments necessary to create a table with a few columns.
They don't go on to detail how to name constraints, create indexes and add foreign keys or similar.
If you're one of the (seemingly very few) people not using code/model-first Entity Framework I've posted this small snippet to help you. It includes how to:
- Create and name a primary key.
- Create and name a foreign key.
- Create and name a default constraint.
- Create and name a non-clustered index.
- Cascade delete.
It does not detail how to create a composite non-clustered index (a non-clustered index on multiple columns).
So, the whole statement is here (note that having a column with the same name as the table will cause problems in EF database-first, the Question property will be renamed Question1):
CREATE TABLE Dog
(
Id INT IDENTITY(-2147483648, 1) CONSTRAINT PK_Dog_Id PRIMARY KEY NOT NULL,
Title NVARCHAR(MAX) NULL,
Name NVARCHAR(MAX) NOT NULL,
OwnerId INT INDEX IX_Dog_Owner NONCLUSTERED
CONSTRAINT FK_Dog_Owner FOREIGN KEY REFERENCES dbo.Owner(Id)
ON DELETE CASCADE,
UserId INT NOT NULL INDEX IX_Dog_User NONCLUSTERED
CONSTRAINT FK_Users_Dog FOREIGN KEY REFERENCES dbo.AspNetUsers(Id),
CreatedDate DATETIME2(0) NOT NULL CONSTRAINT DF_Dog_CreatedDate DEFAULT GETDATE(),
ModifiedDate DATETIME2(0) NOT NULL CONSTRAINT DF_Dog_ModifiedDate DEFAULT GETDATE(),
RowVersion ROWVERSION
)
To run through a few things to note:
INT IDENTITY(-2147483648, 1)
There's an interesting debate about whether to use a GUID or integer for a primary key, I've gone with integer since to me it's more readable, but a quick Google will provide more than enough reading to the interested coder.
I've seeded this primary key with the minimum value for INT, this means values from -2147483648 to 1 aren't wasted.
NVARCHAR(MAX)
NVARCHAR should generally always be used for text columns because it supports Unicode. VARCHAR supports ASCII.
