Major SQLAlchemy features include:
-* An industrial strength ORM, built
+* An industrial strength ORM, built
from the core on the identity map, unit of work,
and data mapper patterns. These patterns
- allow transparent persistence of objects
+ allow transparent persistence of objects
using a declarative configuration system.
Domain models
can be constructed and manipulated naturally,
and changes are synchronized with the
current transaction automatically.
* A relationally-oriented query system, exposing
- the full range of SQL's capabilities
- explicitly, including joins, subqueries,
- correlation, and most everything else,
+ the full range of SQL's capabilities
+ explicitly, including joins, subqueries,
+ correlation, and most everything else,
in terms of the object model.
- Writing queries with the ORM uses the same
- techniques of relational composition you use
+ Writing queries with the ORM uses the same
+ techniques of relational composition you use
when writing SQL. While you can drop into
literal SQL at any time, it's virtually never
needed.
-* A comprehensive and flexible system
+* A comprehensive and flexible system
of eager loading for related collections and objects.
Collections are cached within a session,
- and can be loaded on individual access, all
+ and can be loaded on individual access, all
at once using joins, or by query per collection
across the full result set.
-* A Core SQL construction system and DBAPI
+* A Core SQL construction system and DBAPI
interaction layer. The SQLAlchemy Core is
separate from the ORM and is a full database
abstraction layer in its own right, and includes
- an extensible Python-based SQL expression
- language, schema metadata, connection pooling,
+ an extensible Python-based SQL expression
+ language, schema metadata, connection pooling,
type coercion, and custom types.
-* All primary and foreign key constraints are
+* All primary and foreign key constraints are
assumed to be composite and natural. Surrogate
- integer primary keys are of course still the
+ integer primary keys are of course still the
norm, but SQLAlchemy never assumes or hardcodes
to this model.
* Database introspection and generation. Database
schemas can be "reflected" in one step into
Python structures representing database metadata;
- those same structures can then generate
+ those same structures can then generate
CREATE statements right back out - all within
the Core, independent of the ORM.
that should be fully exposed. SQLAlchemy's
ORM provides an open-ended set of patterns
that allow a developer to construct a custom
- mediation layer between a domain model and
+ mediation layer between a domain model and
a relational schema, turning the so-called
"object relational impedance" issue into
a distant memory.
of both the object model as well as the relational
schema. SQLAlchemy only provides the means
to automate the execution of these decisions.
-* With SQLAlchemy, there's no such thing as
- "the ORM generated a bad query" - you
- retain full control over the structure of
+* With SQLAlchemy, there's no such thing as
+ "the ORM generated a bad query" - you
+ retain full control over the structure of
queries, including how joins are organized,
- how subqueries and correlation is used, what
+ how subqueries and correlation is used, what
columns are requested. Everything SQLAlchemy
does is ultimately the result of a developer-
initiated decision.
* Don't use an ORM if the problem doesn't need one.
SQLAlchemy consists of a Core and separate ORM
component. The Core offers a full SQL expression
- language that allows Pythonic construction
+ language that allows Pythonic construction
of SQL constructs that render directly to SQL
strings for a target database, returning
result sets that are essentially enhanced DBAPI
the start and end of a series of operations.
* Never render a literal value in a SQL statement.
Bound parameters are used to the greatest degree
- possible, allowing query optimizers to cache
+ possible, allowing query optimizers to cache
query plans effectively and making SQL injection
attacks a non-issue.
Installation / Requirements
---------------------------
-Full documentation for installation is at
+Full documentation for installation is at
`Installation <http://www.sqlalchemy.org/docs/intro.html#installation>`_.
Getting Help / Development / Bug reporting
Please refer to the `SQLAlchemy Community Guide <http://www.sqlalchemy.org/support.html>`_.
+Code of Conduct
+---------------
+
+Above all, SQLAlchemy places great emphasis on polite, thoughtful, and
+constructive communication between users and developers.
+Please see our current Code of Conduct at
+`Code of Conduct <http://www.sqlalchemy.org/codeofconduct.html>`_.
+
License
-------