The column length is automatically defined, when developers select a data type. Developers can reset the Length property for a column with a character data type, such as binary, char, nchar, nvarchar, varbinary, or varchar, if they want to increase or decrease the length of acceptable values in that column.  For columns with numeric data types, the length is set by the Precision property. When developers working with SQL Server “Denali”, MS SQL Server 2008 R2 and MS SQL Server 2005 want to modify the length of a columns data type, they should follow the next steps:

1. In Object Explorer, right-click the table with columns for which they want to modify the length and click Design (Modify in SP1 or earlier).

The table opens in Table Designer.

2. In the Column Properties tab, type a length for the column’s data type in the Length field. Developers can edit the Length property for character data types only.

The new length is assigned to the column in the Table Designer after they click outside the grid cell or use the TAB key to move to another grid cell. It takes effect in the database when they save their changes in Table Designer.