Other SQL Clauses
SQLAlchemy ORM also exposes support for other clauses in SQL, such as ORDER BY, GROUP BY, LIMIT, and OFFSET. All of these are supported by this connector:
ORDER BY
The following example sorts by a specified column using the session object's query() method:rs = session.query([CData].[Employee Management].Leave_Types).order_by([CData].[Employee Management].Leave_Types.AnnualRevenue)
for instance in rs:
print("Id: ", instance.Id)
print("ID: ", instance.ID)
print("Leave_Type: ", instance.Leave_Type)
print("---------")
You can also use the session object's execute() method perform an ORDER BY. For example:
rs = session.execute([CData].[Employee Management].Leave_Types_table.select().order_by([CData].[Employee Management].Leave_Types_table.c.AnnualRevenue)) for instance in rs:
GROUP BY
The following example uses the session object's query() method to group records with a specified column:rs = session.query(func.count([CData].[Employee Management].Leave_Types.Id).label("CustomCount"), [CData].[Employee Management].Leave_Types.ID).group_by([CData].[Employee Management].Leave_Types.ID)
for instance in rs:
print("Count: ", instance.CustomCount)
print("ID: ", instance.ID)
print("---------")
You can also use the session object's execute() method to perform a GROUP BY:
rs = session.execute([CData].[Employee Management].Leave_Types_table.select().with_only_columns([func.count([CData].[Employee Management].Leave_Types_table.c.Id).label("CustomCount"), [CData].[Employee Management].Leave_Types_table.c.ID]).group_by([CData].[Employee Management].Leave_Types_table.c.ID))
for instance in rs:
LIMIT and OFFSET
The following example uses the session object's query() method to skip the first 100 records and fetch the following 25:rs = session.query([CData].[Employee Management].Leave_Types).limit(25).offset(100)
for instance in rs:
print("Id: ", instance.Id)
print("ID: ", instance.ID)
print("Leave_Type: ", instance.Leave_Type)
print("---------")
You can also use the session object's execute() method to set a LIMIT or OFFSET:
rs = session.execute([CData].[Employee Management].Leave_Types_table.select().limit(25).offset(100)) for instance in rs: