alter table edit column code example

Example 1: sql change column types

ALTER TABLE table_name
ALTER COLUMN column_name datatype;

-- Example
ALTER TABLE product
ALTER COLUMN description VARCHAR(250);

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 table query sql server change column

ALTER TABLE table_name
  ALTER COLUMN column_name column_type;

Example 4: alter table query sql server change column

ALTER TABLE employees
  ALTER COLUMN last_name VARCHAR(75) NOT NULL;

Example 5: alter table query sql server change column

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