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Creating a Table

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 | 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 EmployerlD 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. Click the Save button on the toolbar to save the table. In the Choose Name dialog enter Persons as the name and click OK to save your table as shown in Figure 2.21. Figure 2.21 Entering the name of the table Note Once you ve saved your table you can return to the table designer at any time by selecting the table in the Tables node of Enterprise Manager right-clicking the table and selecting Design Table. In the rest of this chapter you ll learn how to Get additional information about the columns in a table using the Columns tab. Set the primary key of a table. Set the permissions that allow access to the contents of a table. Create a relationship between tables. Create an index to allow faster access to the information in a table. Create a constraint to restrict values that may be stored in a column. The Columns Tab In the area .