sql server 2019 Adding specific columns automatically while creating a new table code example

Example 1: create column sql server

ALTER TABLE table_name
ADD column_name datatype;

Example 2: Insert and initialize a SQL column with value dependent on another column data

UPDATE table
SET col = new_value
WHERE col = old_value
AND other_col = some_other_value;

UPDATE table
SET col = new_value
WHERE col = old_value
OR other_col = some_other_value;