how to modify column in sql code example

Example 1: sql add column

ALTER TABLE Customers
ADD Email varchar(255);

Example 2: alter table modify column

-- ORACLE 18c
ALTER TABLE table_name 
MODIFY column_name datatype;

-- Example
ALTER TABLE product
MODIFY description VARCHAR2(500 char);

Example 3: alter column sql server

ALTER TABLE table_name

ALTER COLUMN column_name datatype;

Example 4: alter table query sql server change column

ALTER TABLE table_name
  DROP COLUMN column_name;

Example 5: alter table query sql server change column

sp_rename 'employees.last_name', 'lname', 'COLUMN';

Example 6: alter table query sql server change column

sp_rename 'table_name.old_column_name', 'new_column_name', 'COLUMN';