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How to Alter column in SQL Server
You can change the column datatype or increase the length of exiting column. Like Alter table you have to write Alter Column
keyword for column. Syntax is given below.
Alter Table [Table Name] Alter Column [Column Name] [datatype]
For any change in existing column, you have to careful about data. If you will decrease the length then data can be truncate or it will show datatype error If you will change the data type and data is not compatible with new data type.
Alter Table Customers Alter Column Cust_City nvarchar(100)
Alter Table Customers Alter Column Cust_State nvarchar(100)