[sqlite] Table alias not accepted with "delete/update" ?

[Domingo Alvarez Duarte]

Hello !  

Today I'm trying to execute this statememt and it works:  

SELECT * FROM __tables_metadata a WHERE NOT EXISTS(SELECT 1 FROM
sqlite_master where tbl_name=a.name);  

Then I tried this one and it fails:  

DELETE FROM __tables_metadata a WHERE NOT EXISTS(SELECT 1 FROM sqlite_master
where tbl_name=a.name);  

Then I changed it to and it works:  

DELETE FROM __tables_metadata WHERE NOT EXISTS(SELECT 1 FROM sqlite_master
where tbl_name=__tables_metadata.name);  

Then I needed this and it doesn't work (here I'm referring the same table
twice):  

UPDATE __tables_metadata a set list_table_id=NULL where NOT EXISTS(SELECT 1
FROM __tables_metadata WHERE id=a.list_table_id);  

?  

It seems to be a bug/missing implementation ?  

Cheers !