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edited Jan 6, 2023 at 17:26

Super Kai - Kazuya Ito

edited Jan 6, 2023 at 17:26

Super Kai - Kazuya Ito

42.9k
23
259
259

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhereafter database settings in settings.py so I normally runas shown below. *If running the raw query just afterbefore database settings as shown below, error occurs:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

*settings.py is run every time Django Server is run with the command below or every time Django Server is reloaded by writing code so transaction is set every time Django Server is run with the command below or every time Django Server is reloaded by writing code:

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level after database settings in settings.py as shown below. *If running the raw query before database settings, error occurs:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

deleted 2 characters in body

Source Link

edited Jan 3, 2023 at 22:06

Super Kai - Kazuya Ito

edited Jan 3, 2023 at 22:06

Super Kai - Kazuya Ito

42.9k
23
259
259

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

*settings.py is run every time Django Server is run with the command below or every time Django Server is reloaded by changingwriting code so transaction is set every time Django Server is run with the command below or every time Django Server is reloaded by changingwriting code:

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

*settings.py is run every time Django Server is run with the command below or every time Django Server is reloaded by changing code so transaction is set every time Django Server is run with the command below or every time Django Server is reloaded by changing code:

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

added 55 characters in body

Source Link

edited Jan 3, 2023 at 21:12

Super Kai - Kazuya Ito

edited Jan 3, 2023 at 21:12

Super Kai - Kazuya Ito

42.9k
23
259
259

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': {
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}

There are 2 ways to set REPEATABLE READ in Django.

<The 1st way (My recommendation)>

You can run the raw query to set isolation level anywhere in settings.py so I normally run the raw query just after database settings as shown below:

# "settings.py"
from django.db import connection
# ...
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
}
# ↓ ↓ ↓ Set isolation level ↓ ↓ ↓
cursor = connection.cursor()
query = """
 ALTER DATABASE postgres 
 SET DEFAULT_TRANSACTION_ISOLATION 
 TO 'REPEATABLE READ';
 """
cursor.execute(query)
# ↓ ↓ ↓ Check isolation level ↓ ↓ ↓
cursor.execute('SHOW default_transaction_isolation;')
print(cursor.fetchone()) # ('repeatable read',)

python manage.py runserver 0.0.0.0:8000

<The 2nd way>

You can directly set REPEATABLE READ with psql as shown below:

postgres=# ALTER DATABASE postgres SET DEFAULT_TRANSACTION_ISOLATION TO 'REPEATABLE READ';

Actually, what the documentation explains as shown below doesn't work for me with Django 3.2.16 on Windows 11. That's why I show the 2 ways above:

# "settings.py"
import psycopg2.extensions
DATABASES = {
 'default':{
 'ENGINE':'django.db.backends.postgresql',
 'NAME':'postgres',
 'USER':'postgres',
 'PASSWORD':'admin',
 'HOST':'localhost',
 'PORT':'5432',
 },
 'OPTIONS': { # ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ Doesn't work ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓
 'isolation_level': psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE,
 },
}