update column name in sql server code example

Example 1: change column names mssql

--The following example renames the column TerritoryID in the table Sales.SalesTerritory to TerrID in the AdventureWorks database.

EXEC sp_rename 'Sales.SalesTerritory.TerritoryID', 'TerrID', 'COLUMN';

Example 2: append column sql

ALTER TABLE table_name
ADD column_name datatype;

--example
ALTER TABLE Customers
ADD Email varchar(255);

Example 3: change column name in sql

MySQL:
ALTER TABLE Customer CHANGE Address Addr char(50);

Oracle:
ALTER TABLE Customer RENAME COLUMN Address TO Addr;

Example 4: modify column name in tsql

sp_rename 'table_name.old_column', 'new_name', 'COLUMN';

Example 5: change column name sql

ALTER TABLE users
 ALTER COLUMN first username varchar(20);