How to create complex multi model join query set with Django ORM - django

Question

I want to create a query set with multiple tables. I cannot find any resource that helps
Beside some small 2 table join examples, I cannot find any resource that is helpful for this, not in stackoverflow, the Django docs or even in the ORM Cookbook.
Below is firstly the SQL I want to recreate followed by the models classes, simplified for the purpose of this question. They have in fact a LOT more fields.
SELECT doc_uid,
docd_filename,
doct_name,
docd_media_url
FROM vugd_detail,
vug_virtual_user_group,
vugdoc_vug_docs,
doc_documents,
docd_detail,
doct_type
WHERE vugd_vug_uid = vug_uid
AND vugdoc_vug_uid = vug_uid
AND vugdoc_doc_uid = doc_uid
AND docd_doc_uid = doc_uid
AND doct_uid = doc_doct_uid
AND vugd_status = 1
AND docd_status = 1
AND NOW() BETWEEN vugd_start_date AND vugd_end_date
AND NOW() BETWEEN docd_start_date AND docd_end_date
AND vug_uid = {{Some ID}};
class VugVirtualUserGroup(models.Model):
objects = None
vug_uid = models.AutoField(primary_key=True)
vug_name = models.CharField(unique=True, max_length=30)
vug_short_code = models.CharField(max_length=6)
vug_created_on = models.DateTimeField()
vug_created_by = models.CharField(max_length=30)
class Meta:
managed = False
db_table = 'vug_virtual_user_group'
app_label = 'main'
class VugdDetail(models.Model):
objects = None
vugd_uid = models.AutoField(primary_key=True)
vugd_vug_uid = models.ForeignKey(VugVirtualUserGroup, models.DO_NOTHING, db_column='vugd_vug_uid')
vugd_long_name = models.CharField(max_length=50)
vugd_status = models.IntegerField()
vugd_start_date = models.DateTimeField()
vugd_end_date = models.DateTimeField()
class Meta:
managed = False
db_table = 'vugd_detail'
app_label = 'main'
class VugdocVugDocs(models.Model):
onjects = None
vugdoc_uid = models.AutoField(primary_key=True)
vugdoc_vug_uid = models.ForeignKey(VugVirtualUserGroup, models.DO_NOTHING, db_column='vugdoc_vug_uid')
vugdoc_doc_uid = models.ForeignKey(DocDocuments, models.DO_NOTHING, db_column='vugdoc_doc_uid')
class Meta:
managed = False
db_table = 'vugdoc_vug_docs'
app_label = 'main'
class DocdDetail(models.Model):
objects = None
docd_uid = models.AutoField(primary_key=True)
docd_doc_uid = models.ForeignKey(DocDocuments, models.DO_NOTHING, db_column='docd_doc_uid')
docd_filename = models.CharField(max_length=200)
docd_media_url = models.CharField(max_length=300)
docd_status = models.IntegerField()
docd_start_date = models.DateTimeField()
docd_end_date = models.DateTimeField()
class Meta:
managed = False
db_table = 'docd_detail'
app_label = 'main'
class DoctType(models.Model):
objects = None
doct_uid = models.AutoField(primary_key=True)
doct_vug_uid = models.ForeignKey('VugVirtualUserGroup', models.DO_NOTHING, db_column='doct_vug_uid')
doct_name = models.CharField(max_length=30)
doct_start_date = models.DateTimeField()
doct_end_date = models.DateTimeField()
class Meta:
managed = False
db_table = 'doct_type'
app_label = 'main'
class DocDocuments(models.Model):
object = None
doc_uid = models.AutoField(primary_key=True)
doc_doct_uid = models.ForeignKey('DoctType', models.DO_NOTHING, db_column='doc_doct_uid')
class Meta:
managed = False
db_table = 'doc_documents'
app_label = 'main'
As one can see the actual query is not so complicated.
The goal here is just to get the list of valid(active, not deleted) files avilable for a specific VUG(Simple user group), if the group has a valid status.
So if there is any Django ORM experts who can help with what is really a common SQL type that should be should be possible to be converted to a Django ORM script, your help will sincerely be appreciated.

Answer 1

The Django way to query multiple related tables is to chain them using dot notation.
A sudo code example might help point you in the right direction.
vug_virtual_user_group = VugVirtualUserGroup.objects.get(vug_uid="Some ID")
print(f'vug_virtual_user_group {vug_virtual_user_group}')
A lookup using the foreign key to get all related objects
vugdoc_vugdocs = vug_virtual_user_group.vugdocvugdocs_set.all()
print(f'vugdoc_vugdocs {vugdoc_vugdocs}')
This example assumes that the default modelmanger objects is not overridden by objects = None.