create column in table sql code example

Example 1: sql server alter column

ALTER TABLE table_name 
ALTER COLUMN column_name new_data_type(size);

Example 2: create column sql server

ALTER TABLE table_name
ADD column_name datatype;

Example 3: how to make new column in sql

<?php
 
    echo str_replace("john", "jack", "hello i am john"); 
 
?>