Thread: NOT NULL and postgres 6.5.2
Hello all, I have an table like this: CREATE TABLE anzeigen ( ... name varchar(30) NOT NULL, ... ); The following statement _will_ be inserted: INSERT INTO anzeigen ( ... name ...) VALUES ( ..., '', ...); What is my problem? Thanks in advance Stephan Bauer
Stephan Bauer wrote: >Hello all, > >I have an table like this: > >CREATE TABLE anzeigen ( >... > > name varchar(30) NOT NULL, >... >); > >The following statement _will_ be inserted: > >INSERT INTO anzeigen ( ... name...) >VALUES ( ..., '', ...); > >What is my problem? An empty string is not the same as null. It is a real value whereas null is an unknown/undefined/irrelevant value. -- Vote against SPAM: http://www.politik-digital.de/spam/ ======================================== Oliver Elphick Oliver.Elphick@lfix.co.uk Isle of Wight http://www.lfix.co.uk/oliver PGP key from public servers; key ID32B8FAA1 ======================================== "But be ye doers of the word, and not hearers only, deceiving your own selves." James 1:22
Stephan Bauer <stephan_bauer@gmx.de> writes: > CREATE TABLE anzeigen ( > ... > name varchar(30) NOT NULL, > ... > ); > The following statement _will_ be inserted: > INSERT INTO anzeigen ( ... name ...) > VALUES ( ..., '', ...); > What is my problem? An empty string '' is quite different from a NULL. If you want to forbid empty strings you could add a constraint expression, eg, CHECK (name <> ''). regards, tom lane