Please, can someone explain how is it posible for ALTER TABLE to add a primary key column to a table without some intruction that would make it a real PK (NOT NULL and UNIQUE).
prueba=> CREATE TABLE nopk ( prueba(> textito varchar prueba(> ); CREATE TABLE prueba=> INSERT INTO nopk VALUES ('algo de texto'); INSERT 0 1 prueba=> INSERT INTO nopk VALUES ('otro texto'); INSERT 0 1 prueba=> ALTER TABLE nopk ADD COLUMN id INT PRIMARY KEY; NOTICE: ALTER TABLE / ADD PRIMARY KEY creará el índice implícito «nopk_pkey» para la tabla «nopk» ALTER TABLE prueba=> \d nopk Tabla «martin.nopk» Columna | Tipo | Modificadores ---------+-------------------+--------------- textito | character varying | id | integer | not null Índices: «nopk_pkey» PRIMARY KEY, btree (id)
prueba=> SELECT * FROM nopk WHERE id IS NULL; textito | id ---------------+---- algo de texto | otro texto | (2 filas)
So id is a pk with NULL values, which isn't right.
