how to alter a column in sql code example

Example 1: sql add column

ALTER TABLE Customers
ADD Email varchar(255);

Example 2: sql server alter column

ALTER TABLE table_name 
ALTER COLUMN column_name new_data_type(size);

Example 3: sql change column in existing table

'This adds 'NOT NULL' to excisting column counting in the table mytable'
ALTER TABLE mytable ALTER COLUMN counting INT NOT NULL;

Example 4: alter column sql server

ALTER TABLE table_name

ALTER COLUMN column_name datatype;

Example 5: sql alter column

Changes the data type of a table’s column.
Example: In the ‘users’ table, make the column ‘incept_date’ into a
‘datetime’ type.
ALTER TABLE users
ALTER COLUMN incept_date datetime;