abstract public Schema::addField($table, $field, $spec, $keys_new = array())
Add a new field to a table.
Parameters
$table: Name of the table to be altered.
$field: Name of the field to be added.
$spec: The field specification array, as taken from a schema definition. The specification may also contain the key 'initial', the newly created field will be set to the value of the key in all rows. This is most useful for creating NOT NULL columns with no default value in existing tables. Alternativ