Il 19/03/2022 17:35 Christophe Pettus ha scritto:
On Mar 19, 2022, at 05:10, Paolo De Stefani <pa...@paolodestefani.it>
wrote:
Switching to psycopg 3 i have to consider many more differences than i
expected
There have been some changes in the way psycopg2 does parameter
substitution, although that one is an interesting case! You might
consider using IS DISTINCT FROM as Daniele suggested, or just =,
depending on how you want nulls handled.
thanks to all for the suggestions i thimk i will use the '=' operator
what do you mean with 'depending on how you want nulls handled' ???
test4=# create table test (a text, b boolean);
CREATE TABLE
test4=# insert into test values ('aaa', true), ('bbb', false), ('ccc',
null);
INSERT 0 3
test4=# select * from test;
a | b
-----+---
aaa | t
bbb | f
ccc |
(3 rows)
test4=# select * from test where b = true;
a | b
-----+---
aaa | t
(1 row)
test4=# select * from test where b is true;
a | b
-----+---
aaa | t
(1 row)
test4=# select * from test where b = null;
a | b
---+---
(0 rows)
test4=# select * from test where b is null;
a | b
-----+---
ccc |
(1 row)
I will use '= True' or '= False' in psycopg cur.execute with parameter
substitution and 'IS NULL' without parameter when i need to check the
null value
--
Paolo De Stefani
