diff --git a/frappe/database/database.py b/frappe/database/database.py
index 5b99f75938..a7490675ba 100644
--- a/frappe/database/database.py
+++ b/frappe/database/database.py
@@ -73,7 +73,7 @@ class Database:
 		self.host = host or frappe.conf.db_host
 		self.port = port or frappe.conf.db_port
 		self.user = user or frappe.conf.db_name
-		self.db_name = frappe.conf.db_name
+		self.cur_db_name = frappe.conf.db_name
 		self._conn = None
 
 		if ac_name:
@@ -103,7 +103,6 @@ class Database:
 
 	def connect(self):
 		"""Connects to a database as set in `site_config.json`."""
-		self.cur_db_name = self.user
 		self._conn = self.get_connection()
 		self._cursor = self._conn.cursor()
 
@@ -121,6 +120,7 @@ class Database:
 	def use(self, db_name):
 		"""`USE` db_name."""
 		self._conn.select_db(db_name)
+		self.cur_db_name = db_name
 
 	def get_connection(self):
 		"""Return a Database connection object that conforms with https://peps.python.org/pep-0249/#connection-objects."""
diff --git a/frappe/database/mariadb/database.py b/frappe/database/mariadb/database.py
index 00cbd1c332..33eddeaf42 100644
--- a/frappe/database/mariadb/database.py
+++ b/frappe/database/mariadb/database.py
@@ -124,7 +124,7 @@ class MariaDBConnectionUtil:
 		}
 
 		if self.user not in (frappe.flags.root_login, "root"):
-			conn_settings["database"] = self.user
+			conn_settings["database"] = self.cur_db_name
 
 		if self.port:
 			conn_settings["port"] = int(self.port)
@@ -198,7 +198,7 @@ class MariaDBDatabase(MariaDBConnectionUtil, MariaDBExceptionUtil, Database):
 			SUM(`data_length` + `index_length`) / 1024 / 1024 AS `database_size`
 			FROM information_schema.tables WHERE `table_schema` = %s GROUP BY `table_schema`
 			""",
-			self.db_name,
+			self.cur_db_name,
 			as_dict=True,
 		)
 
diff --git a/frappe/database/postgres/database.py b/frappe/database/postgres/database.py
index 48dd55381a..2ed595d5e7 100644
--- a/frappe/database/postgres/database.py
+++ b/frappe/database/postgres/database.py
@@ -162,10 +162,11 @@ class PostgresDatabase(PostgresExceptionUtil, Database):
 	def get_connection(self):
 		conn_settings = {
 			"user": self.user,
-			"dbname": self.user,
 			"host": self.host,
 			"password": self.password,
 		}
+		if self.user not in (frappe.flags.root_login, "root"):
+			conn_settings["dbname"] = self.cur_db_name
 		if self.port:
 			conn_settings["port"] = self.port
 
@@ -199,7 +200,7 @@ class PostgresDatabase(PostgresExceptionUtil, Database):
 	def get_database_size(self):
 		"""Return database size in MB"""
 		db_size = self.sql(
-			"SELECT (pg_database_size(%s) / 1024 / 1024) as database_size", self.db_name, as_dict=True
+			"SELECT (pg_database_size(%s) / 1024 / 1024) as database_size", self.cur_db_name, as_dict=True
 		)
 		return db_size[0].get("database_size")
 
@@ -219,7 +220,7 @@ class PostgresDatabase(PostgresExceptionUtil, Database):
 			where table_catalog='{}'
 				and table_type = 'BASE TABLE'
 				and table_schema='{}'""".format(
-					frappe.conf.db_name, frappe.conf.get("db_schema", "public")
+					self.cur_db_name, frappe.conf.get("db_schema", "public")
 				)
 			)
 		]
diff --git a/frappe/patches/v15_0/remove_implicit_primary_key.py b/frappe/patches/v15_0/remove_implicit_primary_key.py
index 388edca8cd..50becd0bdb 100644
--- a/frappe/patches/v15_0/remove_implicit_primary_key.py
+++ b/frappe/patches/v15_0/remove_implicit_primary_key.py
@@ -44,7 +44,7 @@ def _is_implicit_int_pk(doctype: str) -> bool:
 	values = ()
 	if frappe.db.db_type == "mariadb":
 		query += " and table_schema = %s"
-		values = (frappe.db.db_name,)
+		values = (frappe.db.cur_db_name,)
 
 	col_type = frappe.db.sql(query, values)
 	return bool(col_type and col_type[0][0] == "bigint")