Tài liệu Creating a Table doc

Creating a Table

You can use Enterprise Manager to add a table to a database. In this section, you'll add a

table to the Northwind database to store the details of a person. This table will be called

Persons, and will contain the columns shown in Table 2.8.

Table 2.8: DEFINITION FOR THE COLUMNS OF THE Persons TABLE

COLUMN NAME DATABASE TYPE LENGTH ALLOWS NULL VALUES?

PersonID int 4 No

FirstName nvarchar 15 No

LastName nvarchar 15 No

DateOfBirth datetime 8 Yes

Address nvarchar 50 Yes

EmployerID nchar 5 No

To create a table in the Northwind database, you select the Tables node of the Northwind

database in Enterprise Manager and select Action ➣ New Table. You'll then see the table

designer. Add the columns as shown in Table 2.8 to the table, as shown in Figure 2.20.

Figure 2.20: Adding a new table

Note The length of some of the data types is fixed. For example, the int type always uses

4 bytes of storage space, so you can't change the length of an int column from 4.

Similarly, the datetime type always uses 8 bytes of storage space. You can change

the length of nchar and nvarchar columns because those types are designed to store

variable-length data.