mirrors/django
1
0
Fork 0
mirror of https://github.com/django/django.git synced 2025-08-08 10:59:17 +00:00
Code Issues 32 Releases Wiki Activity

Simplified get_key_columns()/get_relations() introspection methods for PostgreSQL.

Browse Source
This commit is contained in:
Mariusz Felisiak 2019-07-20 15:15:41 +02:00 committed by GitHub
parent 9f11939dd1
commit 842fd620ff
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 4 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
django/db/backends/postgresql/introspection.py
View File

@ -115,8 +115,11 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
Return a dictionary of {field_name: (field_name_other_table, other_table)} Return a dictionary of {field_name: (field_name_other_table, other_table)}
representing all relationships to the given table. representing all relationships to the given table.
""" """
return {row[0]: (row[2], row[1]) for row in self.get_key_columns(cursor, table_name)}
def get_key_columns(self, cursor, table_name):
cursor.execute(""" cursor.execute("""
SELECT c2.relname, a1.attname, a2.attname SELECT a1.attname, c2.relname, a2.attname
FROM pg_constraint con FROM pg_constraint con
LEFT JOIN pg_class c1 ON con.conrelid = c1.oid LEFT JOIN pg_class c1 ON con.conrelid = c1.oid
LEFT JOIN pg_class c2 ON con.confrelid = c2.oid LEFT JOIN pg_class c2 ON con.confrelid = c2.oid
@ -124,22 +127,6 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
LEFT JOIN pg_attribute a2 ON c2.oid = a2.attrelid AND a2.attnum = con.confkey[1] LEFT JOIN pg_attribute a2 ON c2.oid = a2.attrelid AND a2.attnum = con.confkey[1]
WHERE c1.relname = %s AND con.contype = 'f' WHERE c1.relname = %s AND con.contype = 'f'
""", [table_name]) """, [table_name])
return {row[1]: (row[2], row[0]) for row in cursor.fetchall()}
def get_key_columns(self, cursor, table_name):
cursor.execute("""
SELECT kcu.column_name, ccu.table_name AS referenced_table, ccu.column_name AS referenced_column
FROM information_schema.constraint_column_usage ccu
LEFT JOIN information_schema.key_column_usage kcu
ON ccu.constraint_catalog = kcu.constraint_catalog
AND ccu.constraint_schema = kcu.constraint_schema
AND ccu.constraint_name = kcu.constraint_name
LEFT JOIN information_schema.table_constraints tc
ON ccu.constraint_catalog = tc.constraint_catalog
AND ccu.constraint_schema = tc.constraint_schema
AND ccu.constraint_name = tc.constraint_name
WHERE kcu.table_name = %s AND tc.constraint_type = 'FOREIGN KEY'
""", [table_name])
return cursor.fetchall() return cursor.fetchall()
def get_constraints(self, cursor, table_name): def get_constraints(self, cursor, table_name):