Import the database object and the student model, and then run the db. create_all() function to create the tables that are associated with your models. In this case you only have one model, which means that the function call will only create one table in your database: from app import db, Student.
As the documentation says, all() returns the result of the query as a list.
To access the column names we can use the method keys() on the result. It returns a list of column names. Since, we queried only three columns, we can view the same columns on the output as well.
All of the tables are collected in the tables
attribute of the SQLAlchemy MetaData object. To get a list of the names of those tables:
>>> metadata.tables.keys()
['posts', 'comments', 'users']
If you're using the declarative extension, then you probably aren't managing the metadata yourself. Fortunately, the metadata is still present on the baseclass,
>>> Base = sqlalchemy.ext.declarative.declarative_base()
>>> Base.metadata
MetaData(None)
If you are trying to figure out what tables are present in your database, even among the ones you haven't even told SQLAlchemy about yet, then you can use table reflection. SQLAlchemy will then inspect the database and update the metadata with all of the missing tables.
>>> metadata.reflect(engine)
For Postgres, if you have multiple schemas, you'll need to loop thru all the schemas in the engine:
from sqlalchemy import inspect
inspector = inspect(engine)
schemas = inspector.get_schema_names()
for schema in schemas:
print("schema: %s" % schema)
for table_name in inspector.get_table_names(schema=schema):
for column in inspector.get_columns(table_name, schema=schema):
print("Column: %s" % column)
There is a method in engine
object to fetch the list of tables name. engine.table_names()
from sqlalchemy import create_engine
engine = create_engine('postgresql://use:pass@localhost/DBname')
print (engine.table_names())
Within the python interpreter use db.engine.table_names()
$ python
>>> from myapp import db
>>> db.engine.table_names()
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