How do you add a Column with a Case as the default in SQLite?

ALTER TABLE [table_name] ADD COLUMN alloc_strat varchar(25) NOT NULL 
 DEFAULT(CASE
    WHEN (shelf_life_unit = 'Months') THEN 'Min Remaining Shelf Life'
    ELSE 'FIFO')
;

This isn’t working, Is there a way to do this in one sql statement

>Solution :

In SQLite the added columns are not allowed to have expressions are their default.

The following illustrates the syntax of ALTER TABLE ADD COLUMN
statement:

ALTER TABLE table_name ADD COLUMN column_definition; Code language:
SQL (Structured Query Language) (sql) There are some restrictions on
the new column:

The new column cannot have a UNIQUE or PRIMARY KEY constraint. If the
new column has a NOT NULL constraint, you must specify a default value
for the column other than a NULL value. The new column cannot have a
default of CURRENT_TIMESTAMP, CURRENT_DATE, and CURRENT_TIME, or an
expression. If the new column is a foreign key and the foreign key
constraint check is enabled, the new column must accept a default
value NULL.

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