sql-insert format emits NULL as 'None'

[Smylers]

Description

When using the new sql-insert format that @astroshot added in #1366, any NULL value in the data is displayed as the string 'None'.

This obviously corrupts the data when the INSERT statement is run — either inserting a string that shouldn't be there, or where 'None' isn't a valid value (for instance in a numeric field, or where a non-NULL value needs to match a foreign key), just refusing to insert anything.

Demo:

clegg> SELECT NULL::INTEGER AS number, 'None'::TEXT AS word
+--------+------+
| number | word |
|--------+------|
| ⟨NULL⟩ | None |
+--------+------+
SELECT 1
Time: 0.013s
clegg> \T sql-insert
Changed table format to sql-insert
Time: 0.000s
clegg> SELECT NULL::INTEGER AS number, 'None'::TEXT AS word
INSERT INTO ""DUAL"" ("number", "word") VALUES
  ('None', 'None')
;
SELECT 1
Time: 0.002s

Your environment

• Please provide your OS and version information.

  Ubuntu 22.04 LTS

• Please provide your CLI version.

  Version: 3.5.0

• What is the output of pip freeze command.

apt-clone==0.2.1
apturl==0.5.2
ayatana-settings==21.1.28
bcrypt==3.2.0
blinker==1.4
Brlapi==0.8.3
brz-etckeeper==0.0.0
cajarename==21.11.24
chardet==4.0.0
cli-helpers==2.3.0
click==8.0.3
colorama==0.4.4
command-not-found==0.3
configobj==5.0.6
cryptography==3.4.8
cupshelpers==1.0
dbus-python==1.2.18
defer==1.0.6
deja-dup-caja==0.0.9
distro==1.7.0
distro-info===1.1build1
duplicity==0.8.21
Entroware Support Hub==22.4.10
evdev==1.4.0
fasteners==0.14.1
feedparser==6.0.8
folder-color-caja==0.0.86
folder-color-common==0.0.86
future==0.18.2
gpg===1.16.0-unknown
httplib2==0.20.2
importlib-metadata==4.6.4
jeepney==0.7.1
keyring==23.5.0
language-selector==0.1
launchpadlib==1.10.16
lazr.restfulclient==0.14.4
lazr.uri==1.0.6
lockfile==0.12.2
louis==3.20.0
Magnus==1.0.3
Mako==1.1.3
MarkupSafe==2.0.1
mate-hud==22.4.4
mate-menu==22.4.1
mate-tweak==22.4.8
monotonic==1.6
more-itertools==8.10.0
musicbrainzngs==0.7.1
mutagen==1.45.1
netifaces==0.11.0
oauthlib==3.2.0
olefile==0.46
onboard==1.4.1
PAM==0.4.2
paramiko==2.9.3
pendulum==2.1.2
pexpect==4.8.0
pgcli==3.5.0
pgspecial==2.1.0
Pillow==9.0.1
prompt-toolkit==3.0.38
psutil==5.9.0
psycopg==3.1.9
ptyprocess==0.7.0
pulsemixer==1.5.1
pycairo==1.20.1
pycryptodomex==3.11.0
pycups==2.0.1
Pygments==2.15.1
PyGObject==3.42.1
PyICU==2.8.1
pyinotify==0.9.6
PyJWT==2.3.0
pymacaroons==0.13.0
PyNaCl==1.5.0
pyparsing==2.4.7
python-apt==2.4.0+ubuntu1
python-dateutil==2.8.1
python-debian===0.1.43ubuntu1
python-xapp==2.2.1
python-xlib==0.29
pytzdata==2020.1
pyxattr==0.7.2
pyxdg==0.27
PyYAML==5.4.1
quodlibet==4.4.0
reportlab==3.6.8
SecretStorage==3.3.1
setproctitle==1.2.2
sgmllib3k==1.0.0
six==1.16.0
sqlparse==0.4.4
sshtunnel==0.4.0
systemd-python==234
tabulate==0.9.0
typing_extensions==4.6.3
ubuntu-advantage-tools==8001
ubuntu-drivers-common==0.0.0
ufw==0.36.1
unattended-upgrades==0.1
urllib3==1.26.5
usb-creator==0.3.7
wadllib==1.3.6
wcwidth==0.2.6
xdg==5
xkit==0.0.0
youtube-dl==2021.12.17
zipp==1.0.0

[astroshot]

Let me see... I'll fix it later.

[astroshot]

@Smylers I have it fixed in pull request #1409.

[j-bennet]

Fixed via #1409.