List of Changes
===============


2.1.0 beta 3 (2011-05-13)
-------------------------

* Added a fiber linking operator: `{x,y} -> T{x,y}`.
* Provide named attributes for kernel expressions and the complement
  link in a quotient scope: `(program^degree)` generates attribute
  `degree` as an alias for `*1` and `program` as an alias for `^`.
* Added in-selector definitions: `{attr := expr}` is de-sugared to
  `define(attr := expr){attr}`.
* Added `$reference` syntax for inter-scope references.
* Added flow method `fork()`: clone the last node in the flow, e.g.
  `/course?credits=max(fork().credits)`.
* Added flow methods `.filter()` and `.select()` as aliases to `?`
  and `{}` operators.
* Added method `distinct()`: `distinct(table{kernel})` produces
  a flow of unique values of `kernel` as it runs over `table`;
  it is equivalent to `table^kernel`.  `distinct()` and `^` operators
  now filter out NULL values in the kernel.
* Changed semantics of `.` and `{}` expressions: specifier (`.`)
  now allows arbitrary expressions on both sides, selector (`{}`)
  now sets the output columns in the current scope.
* Added syntax `*N`, where `N` is an integer literal, to get the value
  of the `N`-th output column.
* Added addon `tweak.cors`: append `Access-Control-Allow-Origin: *`
  to every HTTP response.
* Added addon `tweak.pgsql.inet`: basic manipulations on values
  of `INET` data type.
* Added addon `tweak.pgsql.view`: determine foreign key relationships
  for views in Postgresql.
* Use `search_path` or its analogues to choose a table when
  the table name is ambiguous.
* Optimized introspection for Oracle.
* Added option `-p` to ask for a password on startup.
* Added shell command `run filename.htsql` to load and execute
  an HTSQL query from a file.
* Many other fixes and documentation updates.


2.1.0 beta 2 (2011-03-29)
-------------------------

* Added support for `datetime` and `time` date types.
* Added support for calculated attributes, `define()` and `where()`
  macros.
* Added addon `tweak.pgsql.catalog`: configure primary and foreign keys
  for `pg_catalog.*` tables.
* Added addon `tweak.schema`: allow addressing a table in a specified schema
  as `<schema>_<table>` identifier.
* Added addon `tweak.autolimit`: add ``LIMIT`` clause to each query.
* Added addon `tweak.pgsql.timeout`: set statement timeout for each query.
* Added Jinja integration demo.
* Many minor fixes and updates.


2.1.0 beta 1 (2011-03-08)
-------------------------

* Ported to MySQL, Oracle and MS SQL Server.
* Added support for projections (`base^kernel`).


2.0.1 final (2011-02-01)
------------------------

* Merged `/:json` and `/:jsonex` formatters; use `/:jsonex` layout
  to avoid CSRF issues.
* Documentation updates.


2.0.0 rc 1 (2011-01-21)
-----------------------

* HTRAF demo is promoted to a standalone project; see
  http://bitbucket.org/prometheus/htraf.
* Added `/:jsonex` format: JSON with extra metadata.
* Documentation updates.


2.0.0 beta 5 (2010-12-14)
-------------------------

* Completed the SQLite backend.
* Completed the standard library.


2.0.0 beta 4 (2010-12-05)
-------------------------

* Refactored peep-hole optimization of the frame tree and SQL
  serialization; refined the generated SQL.
* Refactored the internal API for adding functions.
* Added new (experimental) syntax for infix function call.
* Added an "Examples" section to the documentation.
* Fixed compatibility with Python 2.5.
* Many minor bugfixes, documentation updates, etc.


2.0.0 beta 3 (2010-11-09)
-------------------------

* Refactored the translator from the term tree to the frame tree;
  added a new translation step to collapse nested frames and reduce
  SQL expressions.
* Added the HTRAF demo: use HTSQL with client-side javascript
  to define complex dashboards.
* Added the SSI demo: using HTSQL for web without giving direct access
  to the database.
* Updated the tutorial, minor bugfixes, regression test updates, etc.


2.0.0 beta 2 (2010-10-01)
-------------------------

* Refactored the translator from the expression graph to the term tree.
* Added `Content-Disposition` header to `:json` and `:csv` renderers.
* Merged the tutorial to the repository.


2.0.0 beta 1 (2010-09-21)
-------------------------

* Initial beta release.
* PostgreSQL and SQLite backends are (mostly) supported, the former
  more than the latter.
* The SQL translator needs more work, in particular, the term tree,
  the frame structure and the serializer.
* Lots of functions are either not implemented or missing a proper
  serializer, especially in the SQLite backend.
* Other areas which need more work before the final release: rendering,
  introspection, regression tests and documentation.

