Datalog Educational System Files

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  | DES INSTALLATION (quick guide) |
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Windows Binary Distribution with ACIDE GUI
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- Double-click on des_acide.jar for starting the 
  ACIDE GUI. Requires Java JDK 1.8

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Windows Binary Distribution
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- Double-click on deswin.exe for starting the Windows
  application
- Execute des.exe for starting the console application

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Linux/MacOSX Binary Distribution with ACIDE GUI
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- Add execute permission to files des and des_start,
  typically with:
    chmod +x ./bin/des
    chmod +x ./bin/des_start
  or from the file explorer.
- Check unixodbc is installed
- Start ACIDE from a terminal with:
  java -jar des_acide.jar  
  Requires Java JDK 1.8

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Linux/MacOSX Binary Distribution
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- Add execute permission to files des and des_start,
  typically with:
    chmod +x ./bin/des
    chmod +x ./bin/des_start
  or from the file explorer.
- Check unixodbc is installed
- Start ./des in a terminal from its installation path

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Windows Source Distributions
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1. Create a shortcut in the desktop for running the Prolog 
   interpreter of your choice. 
2. Modify the start directory in the "Properties" dialog box 
   of the shortcut to the installation directory for DES. 
   This allows the system to consult the needed files at startup.
3. Append the following options to the Prolog executable complete 
   filename, depending on the Prolog interpreter you use:
   (a) SICStus Prolog: -l des.pl
   (b) SWI Prolog: -g "ensure_loaded(des)" (remove --win_app if 
     present)
Another alternative is to write a batch file similar to the 
script file described just in the above section.
    
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Linux/MacOSX Source Distributions
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You can write a script for starting DES according to the 
selected Prolog interpreter, as follows:
(a) SICStus Prolog: 
    $SICSTUS -l des.pl 
    Provided that $SICSTUS is the variable which holds 
    the absolute filename of the SICStus Prolog executable.
(b) SWI Prolog: 
    $SWI -g "ensure_loaded(des)"
    Provided that $SWI is the variable which holds the 
    absolute filename of the SWI Prolog executable.

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More Information: 
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- See User Manual
  'Documentation' entry in 
  http://des.sourceforge.net/html/download.html
- http://des.sourceforge.net


Version Devel of DES (released on December, 24th, 2021)
 
"	Enhancements:
o	Intermediate files from a Datalog debugging session are removed
o	Setting fuzzy mode disables non-Datalog languages. As well, setting 
a non-Datalog language in fuzzy mode selects (crisp-)Datalog
o	Commands /ls and /dir accepts a filename as argument. Also, extended
help provided for these commands
o	Text help added for the command /debug_dl_set_node
o	New predicate and function substr with no length
o	Added support for the ALL and ANY quantifiers in the HAVING clause
o	Syntax of PostgreSQL simplified recursive views is supported (the 
same as already provided by DES but adding a RECURSIVE keyword)
o	SQL IS NULL operation extended to deal with expressions
o	Added the value loose for the command /sql_semantic_check, which 
includes more probabiities for false positives, though with more error
detections
o	Avoided some recheckings in SQL semantic warnings
o	Added exception to show internal errors when processing SQL queries
o	New commands:
"	/debug_dl_solutions Display Datalog debugging solutions for the 
current question. TAPI enabled
"	/nodebug Disable debugging in the host Prolog interpreter. Only 
working for source distributions
"	/parse_external_sql Display whether parsing of SQL queries sent to 
external engines is enabled
"	/parse_external_sql Switch Enable or disable parsing of SQL queries 
sent to external engines (on or off, resp.)
"	/unset Var Unset the user variable Var so it becomes no longer 
defined up to a new setting 
"	/unset_flag FlagName Unset the system flag with name FlagName so it 
becomes no longer defined up to a new setting 
"	Changes:
o	The commands /drop_all_relations and /drop_all_tables apply  the 
CASCADE option
o	The command /get_relation renders null internal representation as 
null for non-TAPI invocations. Otherwise, it displays null internal 
representations 
"	Fixed bugs:
o	The file des_pchr.pl was not located were expected and the debugging
session could not proceed
o	Some functions incorrectly propagated semantic bindings, leading to 
false positives for inconsistent conditions
o	Some relations enclosed between parentheses were not parsed
o	Some false positives in semantic warnings for EXCEPT, UNION, 
DIVISION and IN SQL operators
o	Some built-in predicate calls were not reordered to avoid 
instantiation exceptions
o	False positive in semantic warnings with COUNT DISTINCT when several
relations were joined
o	False positive in semantic warnings  for columns without aggregates 
in the HAVING conditions
o	False positive in semantic warnings for conditions over grouped 
columns occurring in the HAVING clause without an aggregate
o	With ALTER TABLE it was possible to add existing column names
o	Type errors in expressions as arguments of built-in infix operators
o	The command /current_flag failed when applied to a user flag
o	Dropping delimited tables in Oracle would fail