DES 3.10 Released

[Fernando Sáenz Pérez]

[Apologies for multiple receptions]

Hello.
This is a mail just for informing that the new release

Datalog Educational System version 3.10
http://des.sourceforge.net

has been launched on January, 21st, 2015, and tested for

SICStus Prolog 4.2.3
SWI-Prolog 6.6.6

Though the current release highlights several enhancements,
maybe the most important can be the possibility to
declaratively debug and trace some external databases
(including DB2, MySQL, Oracle and PostgreSQL) whenever the
external dialect is recognized by DES. As collateral
effects, first, the dependency graph is also available for
these external databases and, second, the SQL view text is
listed along with the metadata (available with the command
/dbschema). On another subject, it is now possible to
inspect an equivalent SQL formulation for RA expressions, in
addition to the already available Datalog compilations. So,
students can examine different but equivalent formulations
(automatically generated) in different query languages. Some
optimizations have been added to enhance performance a bit
(as the incremental building of the dependency graph, the
EDB optimization applied to external relations, and fixpoint
computation of external relations). Also, some new commands
have been added to provide better batch processing control,
and parameters to scripts have been included. Last but not
the least, both the printed and online manual have been
coloured with respect to system keywords and messages.

A complete list of enhancements, changes and fixed bugs is
attached to the end of this message.
Please, see http://des.sourceforge.net for details.

Best regards.



=============================================================
Fernando Saenz Perez
Profesor Titular de Universidad / Associate Professor
Home Page: http://www.fdi.ucm.es/profesor/fernan
Tel: + 34 913947642. Fax: + 34 913947547
Despacho / Office: 435 (4ª planta / 4th floor)
Dept. Ingenieria del Software e Inteligencia Artificial /
Department of Software Engineering and Artificial
Intelligence
Universidad Complutense de Madrid
Facultad de Informatica
C/Profesor Jose Garcia Santesmases, s/n
E - 28040 Madrid. Spain

=============================================================



Version 3.10 of DES (released on January, 21st, 2015)

* Enhancements:
o Tracing and debugging external relations (via ODBC) is
allowed
o SQL debugging with development mode enabled shows the
logic program every time a clause is added
o The PDG and stratification are also built for external
SQL relations when opening an ODBC connection
o The SQL text which defines an external view is listed
for DB2, MySQL, Oracle, and PostgreSQL whenever it is
recognized by the DES SQL dialect (other DBMS's might work
as well, though not tested)
o An external view for which there is no a mate Datalog
predicate is tagged as an extensional predicate so that
only one fixpoint iteration is needed to solve it
o Extensional database optimization also applies to
external relations
o Incremental building of the PDG which improves
performance a bit
o The equivalent SQL statement to a given RA expression
can be inspected by enabling SQL listings with the command
/show_sql on (The equivalent Datalog rules were possible
to show already with the command /show_compilations on)
o Simplified compilations from RA to SQL
o Relaxed requirement for SQL identifiers: SQL keywords
can be used as identifiers for tables, views, and
attributes. In order to disambiguate, it might be
necessary to enclose the identifier between SQL delimiters
o A relation with a name which coincide with the name of a
Datalog metapredicate with the same arity is rejected
o Constants can include escaped single quotes
o Upgraded DDL info messages for external databases
o Parameterized batch processing: Batch files can contain
references to input parameters ($parv1$, $parv2$, ... )
o Coloured printed and online manual
o Updated colors for the console in ACIDE
o New commands:
- /rdg Display the current relation dependency graph,
i.e., the PDG restricted to show only nodes with type
information (tables and views) . TAPI enabled
- /rdg RelName Display the current relation dependency
graph restricted to the first relation found with name
RelName. TAPI enabled
- /rdg RelName/Arity Display the current relation
dependency graph restricted to the relation with name
RelName and Arity. TAPI enabled
- /refresh_db Refresh local metadata from the current
database (either the local, deductive database or an
external DB), clear the cache, and recompute the PDG and
strata. TAPI enabled
- /repeat Number Input Repeat Input as many times as
Number
- /set_default_parameter Index Value Set the default
value for the i-th parameter (denoted by the number
Index) to Value

* Changes:
o System predicates resulting from compilations (starting
with $) only appear in development mode (this applies to
consulting the current PDG and strata, and tracing Datalog
and local SQL queries)
o Nodes in the PDG include DDB tables
o Infix comparisons, built-ins, and MS Access system
tables are no longer part of the PDG
o PDG arcs are ordered by nodes (previously, first were
the positive arcs, then the negative arcs)
o Warning about undefined predicates are only issued when
either inserting the offending rule or recomputing the
whole PDG
o System autorenamings are not shown in displayed SQL
statements
o Built-ins in SQL expressions are capitalized in listings
o Displayed result sets in SQL debugging are ordered
o Oracle connections are restricted to user tables and
views, therefore avoiding to retrieve dozens of system
relations
o All identifiers in system messages are enclosed between
single quotes
o The argument of the command /process must be enclosed
between double quotes (") if it contains blanks
o Calls to recursive relations are not unfolded (both in
the translations from SQL and unfolding user rules when
/unfold on is submitted)
o Deprecated: SQL DROP TABLE Tablenames

* Fixed bugs:
o The SQL Debugger tried to slice tables when they were
not trusted
o References to attribute names in the GROUP BY clause
were not always resolved
o SQL listings including the DIVISION operator printed its
internal representation
o Some metadata for views were retrieved as they were
tables for Oracle databases
o Some ODBC diag exceptions were not formatted in the
display
o Persistence in DB2 connections was faulty for SWI-Prolog
distros
o Listings involving the top and sort RA operators failed
o The SQL ON clause required a blank after it
o Printing expressions in SQL ORDER BY failed in listings
o When adding a rule for a new predicate calling a
restricted one, the PDG did not include the negative
dependency between them



//------------------------------//
// ACIDE 0.16 Release Notes //
// 07/30/2014 //
//------------------------------//


* Enhancements, changes and fixed bugs:
o Improved Datalog and SQL tracer panels
o Node contents displayed by double-click
o Automatic selection and manual location of program rules
for trace nodes
o Better arrangement of graphs
o Improved Database and Data View panels
o A graphical interface for database constraints
o Console, Database and Data View fixes
o Several bugs fixed but presumably others added.


IMPORTANT CAVEATS / KNOWN BUGS:
o Ctrl+Mouse Wheel for resizing font display may take long
time depending on the number of open file editors.
o Opening medium-sized text files may take long time due
to lexical analysis. No progress indicators are provided.
Only when all editor windows are processed they are
displayed.
o As an alpha version, there are expected many bugs and
incomplete functionalities. Please report them to
fer...@sip.ucm.es