From 955e2945b4e2fe5cede5f6bb3f21382618104a32 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Sun, 9 Oct 2022 19:59:10 +0100
Subject: [PATCH 01/12] Default database parameter

---
 sqlalchemy_utils/functions/database.py | 173 ++++++++++++-------------
 1 file changed, 84 insertions(+), 89 deletions(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index d20618e3..2bd1e73e 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -11,7 +11,7 @@
 from .orm import quote
 
 
-def escape_like(string, escape_char='*'):
+def escape_like(string, escape_char="*"):
     """
     Escape the string paremeter used in SQL LIKE expressions.
 
@@ -29,10 +29,9 @@ def escape_like(string, escape_char='*'):
     :param escape_char: escape character
     """
     return (
-        string
-        .replace(escape_char, escape_char * 2)
-        .replace('%', escape_char + '%')
-        .replace('_', escape_char + '_')
+        string.replace(escape_char, escape_char * 2)
+        .replace("%", escape_char + "%")
+        .replace("_", escape_char + "_")
     )
 
 
@@ -82,6 +81,7 @@ def json_sql(value, scalars_to_json=True):
     """
     scalar_convert = sa.text
     if scalars_to_json:
+
         def scalar_convert(a):
             return sa.func.to_json(sa.text(a))
 
@@ -96,10 +96,7 @@ def scalar_convert(a):
         return scalar_convert("'{0}'".format(value))
     elif isinstance(value, Sequence):
         return sa.func.json_build_array(
-            *(
-                json_sql(v, scalars_to_json=False)
-                for v in value
-            )
+            *(json_sql(v, scalars_to_json=False) for v in value)
         )
     elif isinstance(value, (int, float)):
         return scalar_convert(str(value))
@@ -154,6 +151,7 @@ def jsonb_sql(value, scalars_to_jsonb=True):
     """
     scalar_convert = sa.text
     if scalars_to_jsonb:
+
         def scalar_convert(a):
             return sa.func.to_jsonb(sa.text(a))
 
@@ -168,10 +166,7 @@ def scalar_convert(a):
         return scalar_convert("'{0}'".format(value))
     elif isinstance(value, Sequence):
         return sa.func.jsonb_build_array(
-            *(
-                jsonb_sql(v, scalars_to_jsonb=False)
-                for v in value
-            )
+            *(jsonb_sql(v, scalars_to_jsonb=False) for v in value)
         )
     elif isinstance(value, (int, float)):
         return scalar_convert(str(value))
@@ -275,8 +270,8 @@ class Article(Base):
     table = column_or_constraint.table
     if not isinstance(table, sa.Table):
         raise TypeError(
-            'Only columns belonging to Table objects are supported. Given '
-            'column belongs to %r.' % table
+            "Only columns belonging to Table objects are supported. Given "
+            "column belongs to %r." % table
         )
     primary_keys = table.primary_key.columns.values()
     if isinstance(column_or_constraint, sa.ForeignKeyConstraint):
@@ -284,12 +279,8 @@ class Article(Base):
     else:
         columns = [column_or_constraint]
 
-    return (
-        (primary_keys and starts_with(primary_keys, columns)) or
-        any(
-            starts_with(index.columns.values(), columns)
-            for index in table.indexes
-        )
+    return (primary_keys and starts_with(primary_keys, columns)) or any(
+        starts_with(index.columns.values(), columns) for index in table.indexes
     )
 
 
@@ -375,8 +366,8 @@ class Article(Base):
     table = column_or_constraint.table
     if not isinstance(table, sa.Table):
         raise TypeError(
-            'Only columns belonging to Table objects are supported. Given '
-            'column belongs to %r.' % table
+            "Only columns belonging to Table objects are supported. Given "
+            "column belongs to %r." % table
         )
     primary_keys = list(table.primary_key.columns.values())
     if isinstance(column_or_constraint, sa.ForeignKeyConstraint):
@@ -385,13 +376,13 @@ class Article(Base):
         columns = [column_or_constraint]
 
     return (
-        (columns == primary_keys) or
-        any(
+        (columns == primary_keys)
+        or any(
             columns == list(constraint.columns.values())
             for constraint in table.constraints
             if isinstance(constraint, sa.sql.schema.UniqueConstraint)
-        ) or
-        any(
+        )
+        or any(
             columns == list(index.columns.values())
             for index in table.indexes
             if index.unique
@@ -407,16 +398,12 @@ def is_auto_assigned_date_column(column):
     :param column: SQLAlchemy Column object
     """
     return (
-        (
-            isinstance(column.type, sa.DateTime) or
-            isinstance(column.type, sa.Date)
-        ) and
-        (
-            column.default or
-            column.server_default or
-            column.onupdate or
-            column.server_onupdate
-        )
+        isinstance(column.type, sa.DateTime) or isinstance(column.type, sa.Date)
+    ) and (
+        column.default
+        or column.server_default
+        or column.onupdate
+        or column.server_onupdate
     )
 
 
@@ -427,7 +414,7 @@ def _set_url_database(url: sa.engine.url.URL, database):
     :param database: New database to set.
 
     """
-    if hasattr(url, '_replace'):
+    if hasattr(url, "_replace"):
         # Cannot use URL.set() as database may need to be set to None.
         ret = url._replace(database=database)
     else:  # SQLAlchemy <1.4
@@ -447,10 +434,10 @@ def _sqlite_file_exists(database):
     if not os.path.isfile(database) or os.path.getsize(database) < 100:
         return False
 
-    with open(database, 'rb') as f:
+    with open(database, "rb") as f:
         header = f.read(100)
 
-    return header[:16] == b'SQLite format 3\x00'
+    return header[:16] == b"SQLite format 3\x00"
 
 
 def database_exists(url):
@@ -479,9 +466,9 @@ def database_exists(url):
     dialect_name = url.get_dialect().name
     engine = None
     try:
-        if dialect_name == 'postgresql':
+        if dialect_name == "postgresql":
             text = "SELECT 1 FROM pg_database WHERE datname='%s'" % database
-            for db in (database, 'postgres', 'template1', 'template0', None):
+            for db in (database, "postgres", "template1", "template0", None):
                 url = _set_url_database(url, database=db)
                 engine = sa.create_engine(url)
                 try:
@@ -490,24 +477,26 @@ def database_exists(url):
                     pass
             return False
 
-        elif dialect_name == 'mysql':
+        elif dialect_name == "mysql":
             url = _set_url_database(url, database=None)
             engine = sa.create_engine(url)
-            text = ("SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA "
-                    "WHERE SCHEMA_NAME = '%s'" % database)
+            text = (
+                "SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA "
+                "WHERE SCHEMA_NAME = '%s'" % database
+            )
             return bool(_get_scalar_result(engine, sa.text(text)))
 
-        elif dialect_name == 'sqlite':
+        elif dialect_name == "sqlite":
             url = _set_url_database(url, database=None)
             engine = sa.create_engine(url)
             if database:
-                return database == ':memory:' or _sqlite_file_exists(database)
+                return database == ":memory:" or _sqlite_file_exists(database)
             else:
                 # The default SQLAlchemy database is in memory, and :memory: is
                 # not required, thus we should support that use case.
                 return True
         else:
-            text = 'SELECT 1'
+            text = "SELECT 1"
             try:
                 engine = sa.create_engine(url)
                 return bool(_get_scalar_result(engine, sa.text(text)))
@@ -518,7 +507,7 @@ def database_exists(url):
             engine.dispose()
 
 
-def create_database(url, encoding='utf8', template=None):
+def create_database(url, encoding="utf8", template=None, default_db=None):
     """Issue the appropriate CREATE DATABASE statement.
 
     :param url: A SQLAlchemy engine URL.
@@ -545,51 +534,52 @@ def create_database(url, encoding='utf8', template=None):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if dialect_name == 'postgresql':
-        url = _set_url_database(url, database="postgres")
-    elif dialect_name == 'mssql':
-        url = _set_url_database(url, database="master")
-    elif dialect_name == 'cockroachdb':
-        url = _set_url_database(url, database="defaultdb")
-    elif not dialect_name == 'sqlite':
-        url = _set_url_database(url, database=None)
+    if default_db != None:
+        if dialect_name == "postgresql":
+            url = _set_url_database(url, database="postgres")
+        elif dialect_name == "mssql":
+            url = _set_url_database(url, database="master")
+        elif dialect_name == "cockroachdb":
+            url = _set_url_database(url, database="defaultdb")
+        elif not dialect_name == "sqlite":
+            url = _set_url_database(url, database=None)
+    else:
+        url = _set_url_database(url, database=default_db)
 
-    if (dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}) \
-            or (dialect_name == 'postgresql' and dialect_driver in {
-            'asyncpg', 'pg8000', 'psycopg2', 'psycopg2cffi'}):
-        engine = sa.create_engine(url, isolation_level='AUTOCOMMIT')
+    if (dialect_name == "mssql" and dialect_driver in {"pymssql", "pyodbc"}) or (
+        dialect_name == "postgresql"
+        and dialect_driver in {"asyncpg", "pg8000", "psycopg2", "psycopg2cffi"}
+    ):
+        engine = sa.create_engine(url, isolation_level="AUTOCOMMIT")
     else:
         engine = sa.create_engine(url)
 
-    if dialect_name == 'postgresql':
+    if dialect_name == "postgresql":
         if not template:
-            template = 'template1'
+            template = "template1"
 
         text = "CREATE DATABASE {0} ENCODING '{1}' TEMPLATE {2}".format(
-            quote(engine, database),
-            encoding,
-            quote(engine, template)
+            quote(engine, database), encoding, quote(engine, template)
         )
 
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
-    elif dialect_name == 'mysql':
+    elif dialect_name == "mysql":
         text = "CREATE DATABASE {0} CHARACTER SET = '{1}'".format(
-            quote(engine, database),
-            encoding
+            quote(engine, database), encoding
         )
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
-    elif dialect_name == 'sqlite' and database != ':memory:':
+    elif dialect_name == "sqlite" and database != ":memory:":
         if database:
             with engine.begin() as connection:
                 connection.execute(sa.text("CREATE TABLE DB(id int);"))
                 connection.execute(sa.text("DROP TABLE DB;"))
 
     else:
-        text = 'CREATE DATABASE {0}'.format(quote(engine, database))
+        text = "CREATE DATABASE {0}".format(quote(engine, database))
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
@@ -614,46 +604,51 @@ def drop_database(url):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if dialect_name == 'postgresql':
+    if dialect_name == "postgresql":
         url = _set_url_database(url, database="postgres")
-    elif dialect_name == 'mssql':
+    elif dialect_name == "mssql":
         url = _set_url_database(url, database="master")
-    elif dialect_name == 'cockroachdb':
+    elif dialect_name == "cockroachdb":
         url = _set_url_database(url, database="defaultdb")
-    elif not dialect_name == 'sqlite':
+    elif not dialect_name == "sqlite":
         url = _set_url_database(url, database=None)
 
-    if dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}:
-        engine = sa.create_engine(url, connect_args={'autocommit': True})
-    elif dialect_name == 'postgresql' and dialect_driver in {
-            'asyncpg', 'pg8000', 'psycopg2', 'psycopg2cffi'}:
-        engine = sa.create_engine(url, isolation_level='AUTOCOMMIT')
+    if dialect_name == "mssql" and dialect_driver in {"pymssql", "pyodbc"}:
+        engine = sa.create_engine(url, connect_args={"autocommit": True})
+    elif dialect_name == "postgresql" and dialect_driver in {
+        "asyncpg",
+        "pg8000",
+        "psycopg2",
+        "psycopg2cffi",
+    }:
+        engine = sa.create_engine(url, isolation_level="AUTOCOMMIT")
     else:
         engine = sa.create_engine(url)
 
-    if dialect_name == 'sqlite' and database != ':memory:':
+    if dialect_name == "sqlite" and database != ":memory:":
         if database:
             os.remove(database)
-    elif dialect_name == 'postgresql':
+    elif dialect_name == "postgresql":
         with engine.begin() as connection:
             # Disconnect all users from the database we are dropping.
             version = connection.dialect.server_version_info
-            pid_column = (
-                'pid' if (version >= (9, 2)) else 'procpid'
-            )
-            text = '''
+            pid_column = "pid" if (version >= (9, 2)) else "procpid"
+            text = """
             SELECT pg_terminate_backend(pg_stat_activity.%(pid_column)s)
             FROM pg_stat_activity
             WHERE pg_stat_activity.datname = '%(database)s'
             AND %(pid_column)s <> pg_backend_pid();
-            ''' % {'pid_column': pid_column, 'database': database}
+            """ % {
+                "pid_column": pid_column,
+                "database": database,
+            }
             connection.execute(sa.text(text))
 
             # Drop the database.
-            text = 'DROP DATABASE {0}'.format(quote(connection, database))
+            text = "DROP DATABASE {0}".format(quote(connection, database))
             connection.execute(sa.text(text))
     else:
-        text = 'DROP DATABASE {0}'.format(quote(engine, database))
+        text = "DROP DATABASE {0}".format(quote(engine, database))
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 

From 3b97df1529ca6cdbfcf1da6f95456a6329556e20 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Sun, 9 Oct 2022 20:25:00 +0100
Subject: [PATCH 02/12] logic correction

---
 sqlalchemy_utils/functions/database.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 2bd1e73e..f47199dd 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -534,7 +534,7 @@ def create_database(url, encoding="utf8", template=None, default_db=None):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if default_db != None:
+    if default_db == None:
         if dialect_name == "postgresql":
             url = _set_url_database(url, database="postgres")
         elif dialect_name == "mssql":

From 11d181630b6dd698650cd735e070379308ad6826 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:08:11 +0100
Subject: [PATCH 03/12] Revert "logic correction"

This reverts commit 3b97df1529ca6cdbfcf1da6f95456a6329556e20.
---
 sqlalchemy_utils/functions/database.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index f47199dd..2bd1e73e 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -534,7 +534,7 @@ def create_database(url, encoding="utf8", template=None, default_db=None):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if default_db == None:
+    if default_db != None:
         if dialect_name == "postgresql":
             url = _set_url_database(url, database="postgres")
         elif dialect_name == "mssql":

From 3cfb14575890e2b02add53d8acc7b7e4ebb322cc Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:08:45 +0100
Subject: [PATCH 04/12] Revert "Default database parameter"

This reverts commit 955e2945b4e2fe5cede5f6bb3f21382618104a32.
---
 sqlalchemy_utils/functions/database.py | 173 +++++++++++++------------
 1 file changed, 89 insertions(+), 84 deletions(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 2bd1e73e..d20618e3 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -11,7 +11,7 @@
 from .orm import quote
 
 
-def escape_like(string, escape_char="*"):
+def escape_like(string, escape_char='*'):
     """
     Escape the string paremeter used in SQL LIKE expressions.
 
@@ -29,9 +29,10 @@ def escape_like(string, escape_char="*"):
     :param escape_char: escape character
     """
     return (
-        string.replace(escape_char, escape_char * 2)
-        .replace("%", escape_char + "%")
-        .replace("_", escape_char + "_")
+        string
+        .replace(escape_char, escape_char * 2)
+        .replace('%', escape_char + '%')
+        .replace('_', escape_char + '_')
     )
 
 
@@ -81,7 +82,6 @@ def json_sql(value, scalars_to_json=True):
     """
     scalar_convert = sa.text
     if scalars_to_json:
-
         def scalar_convert(a):
             return sa.func.to_json(sa.text(a))
 
@@ -96,7 +96,10 @@ def scalar_convert(a):
         return scalar_convert("'{0}'".format(value))
     elif isinstance(value, Sequence):
         return sa.func.json_build_array(
-            *(json_sql(v, scalars_to_json=False) for v in value)
+            *(
+                json_sql(v, scalars_to_json=False)
+                for v in value
+            )
         )
     elif isinstance(value, (int, float)):
         return scalar_convert(str(value))
@@ -151,7 +154,6 @@ def jsonb_sql(value, scalars_to_jsonb=True):
     """
     scalar_convert = sa.text
     if scalars_to_jsonb:
-
         def scalar_convert(a):
             return sa.func.to_jsonb(sa.text(a))
 
@@ -166,7 +168,10 @@ def scalar_convert(a):
         return scalar_convert("'{0}'".format(value))
     elif isinstance(value, Sequence):
         return sa.func.jsonb_build_array(
-            *(jsonb_sql(v, scalars_to_jsonb=False) for v in value)
+            *(
+                jsonb_sql(v, scalars_to_jsonb=False)
+                for v in value
+            )
         )
     elif isinstance(value, (int, float)):
         return scalar_convert(str(value))
@@ -270,8 +275,8 @@ class Article(Base):
     table = column_or_constraint.table
     if not isinstance(table, sa.Table):
         raise TypeError(
-            "Only columns belonging to Table objects are supported. Given "
-            "column belongs to %r." % table
+            'Only columns belonging to Table objects are supported. Given '
+            'column belongs to %r.' % table
         )
     primary_keys = table.primary_key.columns.values()
     if isinstance(column_or_constraint, sa.ForeignKeyConstraint):
@@ -279,8 +284,12 @@ class Article(Base):
     else:
         columns = [column_or_constraint]
 
-    return (primary_keys and starts_with(primary_keys, columns)) or any(
-        starts_with(index.columns.values(), columns) for index in table.indexes
+    return (
+        (primary_keys and starts_with(primary_keys, columns)) or
+        any(
+            starts_with(index.columns.values(), columns)
+            for index in table.indexes
+        )
     )
 
 
@@ -366,8 +375,8 @@ class Article(Base):
     table = column_or_constraint.table
     if not isinstance(table, sa.Table):
         raise TypeError(
-            "Only columns belonging to Table objects are supported. Given "
-            "column belongs to %r." % table
+            'Only columns belonging to Table objects are supported. Given '
+            'column belongs to %r.' % table
         )
     primary_keys = list(table.primary_key.columns.values())
     if isinstance(column_or_constraint, sa.ForeignKeyConstraint):
@@ -376,13 +385,13 @@ class Article(Base):
         columns = [column_or_constraint]
 
     return (
-        (columns == primary_keys)
-        or any(
+        (columns == primary_keys) or
+        any(
             columns == list(constraint.columns.values())
             for constraint in table.constraints
             if isinstance(constraint, sa.sql.schema.UniqueConstraint)
-        )
-        or any(
+        ) or
+        any(
             columns == list(index.columns.values())
             for index in table.indexes
             if index.unique
@@ -398,12 +407,16 @@ def is_auto_assigned_date_column(column):
     :param column: SQLAlchemy Column object
     """
     return (
-        isinstance(column.type, sa.DateTime) or isinstance(column.type, sa.Date)
-    ) and (
-        column.default
-        or column.server_default
-        or column.onupdate
-        or column.server_onupdate
+        (
+            isinstance(column.type, sa.DateTime) or
+            isinstance(column.type, sa.Date)
+        ) and
+        (
+            column.default or
+            column.server_default or
+            column.onupdate or
+            column.server_onupdate
+        )
     )
 
 
@@ -414,7 +427,7 @@ def _set_url_database(url: sa.engine.url.URL, database):
     :param database: New database to set.
 
     """
-    if hasattr(url, "_replace"):
+    if hasattr(url, '_replace'):
         # Cannot use URL.set() as database may need to be set to None.
         ret = url._replace(database=database)
     else:  # SQLAlchemy <1.4
@@ -434,10 +447,10 @@ def _sqlite_file_exists(database):
     if not os.path.isfile(database) or os.path.getsize(database) < 100:
         return False
 
-    with open(database, "rb") as f:
+    with open(database, 'rb') as f:
         header = f.read(100)
 
-    return header[:16] == b"SQLite format 3\x00"
+    return header[:16] == b'SQLite format 3\x00'
 
 
 def database_exists(url):
@@ -466,9 +479,9 @@ def database_exists(url):
     dialect_name = url.get_dialect().name
     engine = None
     try:
-        if dialect_name == "postgresql":
+        if dialect_name == 'postgresql':
             text = "SELECT 1 FROM pg_database WHERE datname='%s'" % database
-            for db in (database, "postgres", "template1", "template0", None):
+            for db in (database, 'postgres', 'template1', 'template0', None):
                 url = _set_url_database(url, database=db)
                 engine = sa.create_engine(url)
                 try:
@@ -477,26 +490,24 @@ def database_exists(url):
                     pass
             return False
 
-        elif dialect_name == "mysql":
+        elif dialect_name == 'mysql':
             url = _set_url_database(url, database=None)
             engine = sa.create_engine(url)
-            text = (
-                "SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA "
-                "WHERE SCHEMA_NAME = '%s'" % database
-            )
+            text = ("SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA "
+                    "WHERE SCHEMA_NAME = '%s'" % database)
             return bool(_get_scalar_result(engine, sa.text(text)))
 
-        elif dialect_name == "sqlite":
+        elif dialect_name == 'sqlite':
             url = _set_url_database(url, database=None)
             engine = sa.create_engine(url)
             if database:
-                return database == ":memory:" or _sqlite_file_exists(database)
+                return database == ':memory:' or _sqlite_file_exists(database)
             else:
                 # The default SQLAlchemy database is in memory, and :memory: is
                 # not required, thus we should support that use case.
                 return True
         else:
-            text = "SELECT 1"
+            text = 'SELECT 1'
             try:
                 engine = sa.create_engine(url)
                 return bool(_get_scalar_result(engine, sa.text(text)))
@@ -507,7 +518,7 @@ def database_exists(url):
             engine.dispose()
 
 
-def create_database(url, encoding="utf8", template=None, default_db=None):
+def create_database(url, encoding='utf8', template=None):
     """Issue the appropriate CREATE DATABASE statement.
 
     :param url: A SQLAlchemy engine URL.
@@ -534,52 +545,51 @@ def create_database(url, encoding="utf8", template=None, default_db=None):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if default_db != None:
-        if dialect_name == "postgresql":
-            url = _set_url_database(url, database="postgres")
-        elif dialect_name == "mssql":
-            url = _set_url_database(url, database="master")
-        elif dialect_name == "cockroachdb":
-            url = _set_url_database(url, database="defaultdb")
-        elif not dialect_name == "sqlite":
-            url = _set_url_database(url, database=None)
-    else:
-        url = _set_url_database(url, database=default_db)
+    if dialect_name == 'postgresql':
+        url = _set_url_database(url, database="postgres")
+    elif dialect_name == 'mssql':
+        url = _set_url_database(url, database="master")
+    elif dialect_name == 'cockroachdb':
+        url = _set_url_database(url, database="defaultdb")
+    elif not dialect_name == 'sqlite':
+        url = _set_url_database(url, database=None)
 
-    if (dialect_name == "mssql" and dialect_driver in {"pymssql", "pyodbc"}) or (
-        dialect_name == "postgresql"
-        and dialect_driver in {"asyncpg", "pg8000", "psycopg2", "psycopg2cffi"}
-    ):
-        engine = sa.create_engine(url, isolation_level="AUTOCOMMIT")
+    if (dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}) \
+            or (dialect_name == 'postgresql' and dialect_driver in {
+            'asyncpg', 'pg8000', 'psycopg2', 'psycopg2cffi'}):
+        engine = sa.create_engine(url, isolation_level='AUTOCOMMIT')
     else:
         engine = sa.create_engine(url)
 
-    if dialect_name == "postgresql":
+    if dialect_name == 'postgresql':
         if not template:
-            template = "template1"
+            template = 'template1'
 
         text = "CREATE DATABASE {0} ENCODING '{1}' TEMPLATE {2}".format(
-            quote(engine, database), encoding, quote(engine, template)
+            quote(engine, database),
+            encoding,
+            quote(engine, template)
         )
 
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
-    elif dialect_name == "mysql":
+    elif dialect_name == 'mysql':
         text = "CREATE DATABASE {0} CHARACTER SET = '{1}'".format(
-            quote(engine, database), encoding
+            quote(engine, database),
+            encoding
         )
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
-    elif dialect_name == "sqlite" and database != ":memory:":
+    elif dialect_name == 'sqlite' and database != ':memory:':
         if database:
             with engine.begin() as connection:
                 connection.execute(sa.text("CREATE TABLE DB(id int);"))
                 connection.execute(sa.text("DROP TABLE DB;"))
 
     else:
-        text = "CREATE DATABASE {0}".format(quote(engine, database))
+        text = 'CREATE DATABASE {0}'.format(quote(engine, database))
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 
@@ -604,51 +614,46 @@ def drop_database(url):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if dialect_name == "postgresql":
+    if dialect_name == 'postgresql':
         url = _set_url_database(url, database="postgres")
-    elif dialect_name == "mssql":
+    elif dialect_name == 'mssql':
         url = _set_url_database(url, database="master")
-    elif dialect_name == "cockroachdb":
+    elif dialect_name == 'cockroachdb':
         url = _set_url_database(url, database="defaultdb")
-    elif not dialect_name == "sqlite":
+    elif not dialect_name == 'sqlite':
         url = _set_url_database(url, database=None)
 
-    if dialect_name == "mssql" and dialect_driver in {"pymssql", "pyodbc"}:
-        engine = sa.create_engine(url, connect_args={"autocommit": True})
-    elif dialect_name == "postgresql" and dialect_driver in {
-        "asyncpg",
-        "pg8000",
-        "psycopg2",
-        "psycopg2cffi",
-    }:
-        engine = sa.create_engine(url, isolation_level="AUTOCOMMIT")
+    if dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}:
+        engine = sa.create_engine(url, connect_args={'autocommit': True})
+    elif dialect_name == 'postgresql' and dialect_driver in {
+            'asyncpg', 'pg8000', 'psycopg2', 'psycopg2cffi'}:
+        engine = sa.create_engine(url, isolation_level='AUTOCOMMIT')
     else:
         engine = sa.create_engine(url)
 
-    if dialect_name == "sqlite" and database != ":memory:":
+    if dialect_name == 'sqlite' and database != ':memory:':
         if database:
             os.remove(database)
-    elif dialect_name == "postgresql":
+    elif dialect_name == 'postgresql':
         with engine.begin() as connection:
             # Disconnect all users from the database we are dropping.
             version = connection.dialect.server_version_info
-            pid_column = "pid" if (version >= (9, 2)) else "procpid"
-            text = """
+            pid_column = (
+                'pid' if (version >= (9, 2)) else 'procpid'
+            )
+            text = '''
             SELECT pg_terminate_backend(pg_stat_activity.%(pid_column)s)
             FROM pg_stat_activity
             WHERE pg_stat_activity.datname = '%(database)s'
             AND %(pid_column)s <> pg_backend_pid();
-            """ % {
-                "pid_column": pid_column,
-                "database": database,
-            }
+            ''' % {'pid_column': pid_column, 'database': database}
             connection.execute(sa.text(text))
 
             # Drop the database.
-            text = "DROP DATABASE {0}".format(quote(connection, database))
+            text = 'DROP DATABASE {0}'.format(quote(connection, database))
             connection.execute(sa.text(text))
     else:
-        text = "DROP DATABASE {0}".format(quote(engine, database))
+        text = 'DROP DATABASE {0}'.format(quote(engine, database))
         with engine.begin() as connection:
             connection.execute(sa.text(text))
 

From fddbe343318a831308251207bed4d273b14be8b4 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:10:56 +0100
Subject: [PATCH 05/12] Update database.py

---
 sqlalchemy_utils/functions/database.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 7bc2ff69..95d4a6c7 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -564,6 +564,7 @@ def create_database(url, encoding='utf8', template=None):
     if dialect_name == 'postgresql':
         if not template:
             template = "template1"
+
         text = "CREATE DATABASE {} ENCODING '{}' TEMPLATE {}".format(
             quote(engine, database),
             encoding,
@@ -572,6 +573,7 @@ def create_database(url, encoding='utf8', template=None):
 
         with engine.begin() as connection:
             connection.execute(sa.text(text))
+            
     elif dialect_name == 'mysql':
         text = "CREATE DATABASE {} CHARACTER SET = '{}'".format(
             quote(engine, database),

From 9e7717c286b60a845431b6decaedf5620dac3355 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:11:27 +0100
Subject: [PATCH 06/12] Update database.py

---
 sqlalchemy_utils/functions/database.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 95d4a6c7..1be92a85 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -563,7 +563,7 @@ def create_database(url, encoding='utf8', template=None):
 
     if dialect_name == 'postgresql':
         if not template:
-            template = "template1"
+            template = 'template1'
 
         text = "CREATE DATABASE {} ENCODING '{}' TEMPLATE {}".format(
             quote(engine, database),
@@ -573,7 +573,7 @@ def create_database(url, encoding='utf8', template=None):
 
         with engine.begin() as connection:
             connection.execute(sa.text(text))
-            
+
     elif dialect_name == 'mysql':
         text = "CREATE DATABASE {} CHARACTER SET = '{}'".format(
             quote(engine, database),

From 0cd98df5ff46969be1ffe899ad26859c2329d5bf Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:12:42 +0100
Subject: [PATCH 07/12] default db override no formatting

---
 sqlalchemy_utils/functions/database.py | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 1be92a85..299a3151 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -518,7 +518,7 @@ def database_exists(url):
             engine.dispose()
 
 
-def create_database(url, encoding='utf8', template=None):
+def create_database(url, encoding='utf8', template=None, default_db=None):
     """Issue the appropriate CREATE DATABASE statement.
 
     :param url: A SQLAlchemy engine URL.
@@ -553,6 +553,18 @@ def create_database(url, encoding='utf8', template=None):
         url = _set_url_database(url, database="defaultdb")
     elif not dialect_name == 'sqlite':
         url = _set_url_database(url, database=None)
+    
+    if default_db != None:
+         if dialect_name == "postgresql":
+             url = _set_url_database(url, database="postgres")
+         elif dialect_name == "mssql":
+             url = _set_url_database(url, database="master")
+         elif dialect_name == "cockroachdb":
+             url = _set_url_database(url, database="defaultdb")
+         elif not dialect_name == "sqlite":
+             url = _set_url_database(url, database=None)
+     else:
+         url = _set_url_database(url, database=default_db)
 
     if (dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}) \
             or (dialect_name == 'postgresql' and dialect_driver in {

From 81e4ecf518e45ed78055222357c888ff4862dc3e Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:13:19 +0100
Subject: [PATCH 08/12] whitespace

---
 sqlalchemy_utils/functions/database.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 299a3151..32232fe5 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -563,7 +563,7 @@ def create_database(url, encoding='utf8', template=None, default_db=None):
              url = _set_url_database(url, database="defaultdb")
          elif not dialect_name == "sqlite":
              url = _set_url_database(url, database=None)
-     else:
+    else:
          url = _set_url_database(url, database=default_db)
 
     if (dialect_name == 'mssql' and dialect_driver in {'pymssql', 'pyodbc'}) \

From 6d526586c0f866c75f47603eb3dedb9fb92c95a9 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:14:35 +0100
Subject: [PATCH 09/12] codebase style preservation

---
 sqlalchemy_utils/functions/database.py | 17 ++++-------------
 1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index 32232fe5..eaab43ab 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -545,23 +545,14 @@ def create_database(url, encoding='utf8', template=None, default_db=None):
     dialect_name = url.get_dialect().name
     dialect_driver = url.get_dialect().driver
 
-    if dialect_name == 'postgresql':
-        url = _set_url_database(url, database="postgres")
-    elif dialect_name == 'mssql':
-        url = _set_url_database(url, database="master")
-    elif dialect_name == 'cockroachdb':
-        url = _set_url_database(url, database="defaultdb")
-    elif not dialect_name == 'sqlite':
-        url = _set_url_database(url, database=None)
-    
     if default_db != None:
-         if dialect_name == "postgresql":
+         if dialect_name == 'postgresql':
              url = _set_url_database(url, database="postgres")
-         elif dialect_name == "mssql":
+         elif dialect_name == 'mssql':
              url = _set_url_database(url, database="master")
-         elif dialect_name == "cockroachdb":
+         elif dialect_name == 'cockroachdb':
              url = _set_url_database(url, database="defaultdb")
-         elif not dialect_name == "sqlite":
+         elif not dialect_name == 'sqlite':
              url = _set_url_database(url, database=None)
     else:
          url = _set_url_database(url, database=default_db)

From c610ec62e238a2573ee2793f0592ac34d459eb88 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Thu, 27 Oct 2022 02:19:34 +0100
Subject: [PATCH 10/12] Documentation

---
 sqlalchemy_utils/functions/database.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index eaab43ab..b37f0d95 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -526,6 +526,7 @@ def create_database(url, encoding='utf8', template=None, default_db=None):
     :param template:
         The name of the template from which to create the new database. At the
         moment only supported by PostgreSQL driver.
+    :param defualt_db: Overwrite the defualt database used when connecting.
 
     To create a database, you can pass a simple URL that would have
     been passed to ``create_engine``. ::

From ec7ab4f9aae469b244107a51d272695cb6abaadd Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Fri, 28 Oct 2022 14:44:06 +0100
Subject: [PATCH 11/12] typo

---
 sqlalchemy_utils/functions/database.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index b37f0d95..e31e1e42 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -526,7 +526,7 @@ def create_database(url, encoding='utf8', template=None, default_db=None):
     :param template:
         The name of the template from which to create the new database. At the
         moment only supported by PostgreSQL driver.
-    :param defualt_db: Overwrite the defualt database used when connecting.
+    :param defualt_db: Overwrite the default database used when connecting.
 
     To create a database, you can pass a simple URL that would have
     been passed to ``create_engine``. ::

From 6d87c2af342f6e3525d18c4cee6e86de897a51e6 Mon Sep 17 00:00:00 2001
From: George Taylor <george@gpst.me>
Date: Tue, 15 Nov 2022 23:08:18 +0000
Subject: [PATCH 12/12] support for named default_db in database_exists

---
 sqlalchemy_utils/functions/database.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sqlalchemy_utils/functions/database.py b/sqlalchemy_utils/functions/database.py
index e31e1e42..c9c1a426 100644
--- a/sqlalchemy_utils/functions/database.py
+++ b/sqlalchemy_utils/functions/database.py
@@ -453,10 +453,11 @@ def _sqlite_file_exists(database):
     return header[:16] == b'SQLite format 3\x00'
 
 
-def database_exists(url):
+def database_exists(url, default_db=None):
     """Check if a database exists.
 
     :param url: A SQLAlchemy engine URL.
+    :param default_db: The default database to use instead of requiring standard
 
     Performs backend-specific testing to quickly determine if a database
     exists on the server. ::
@@ -481,7 +482,7 @@ def database_exists(url):
     try:
         if dialect_name == 'postgresql':
             text = "SELECT 1 FROM pg_database WHERE datname='%s'" % database
-            for db in (database, 'postgres', 'template1', 'template0', None):
+            for db in (database, default_db or 'postgres', 'template1', 'template0', None):
                 url = _set_url_database(url, database=db)
                 engine = sa.create_engine(url)
                 try: