Tables: Creating and Removing

Tables are key database objects in MS SQL Server and are comprised of columns and rows. The columns define the type of information that is stored and the rows contain the values for those columns.

Before creating a table, we must decide how many columns the table will have, the names and data types of those columns, and whether or not these columns can have empty values.

Common data types

MS SQL Server supports a variety of data types, but let’s discuss the most common ones we might encounter in real-life database systems.

The INT and BIGINT data types

The INT data type represents a whole number ranging from -2,147,483,648 to 2,147,483,647. For smaller or larger values, we can use the BIGINT data type.

The VARCHAR and NVARCHAR data types

To store textual information, we can use either VARCHAR or NVARCHAR. Both data types are used for variable-length text values. When creating a column or a variable of type VARCHAR or NVARCHAR, we must provide the maximum length the column or a variable can hold. For example, VARCHAR(10) can have a text value that is a maximum of 10 characters long. If we do not want to impose a limit, we can use the MAX keyword (NVARCHAR(MAX) ...