added AQL example queries

Ahuacatl/ahuacatl-optimiser.c

@@ -122,6 +122,10 @@ static void PatchForLoops (TRI_aql_context_t* const context) {
       continue;
     } 
     
+    if (!scope->_ranges) {
+      continue;
+    } 
+    
     // we found a for loop, inspect it
     prefix = TRI_Concatenate2String(scope->_variableName, ".");
 
@@ -130,7 +134,7 @@ static void PatchForLoops (TRI_aql_context_t* const context) {
       TRI_SetErrorContextAql(context, TRI_ERROR_OUT_OF_MEMORY, NULL);
       return;
     }
-  
+ 
     // iterate over all possible field accesses we found in this scope
     len = scope->_ranges->_length;
     for (j = 0; j < len; ++j) {

Doxygen/Examples.Ahuacatl/aqlexample-collection

@@ -0,0 +1,42 @@
+/* return 5 documents from a users collection, unaltered */
+FOR u IN users 
+  LIMIT 0, 5
+  RETURN u
+
+[ { "_id" : "9259836/10505020", "_rev" : 10505020, "active" : true, "id" : 100, "age" : 37, "name" : "John", "gender" : "m" }, 
+  { "_id" : "9259836/11553596", "_rev" : 11553596, "active" : true, "id" : 107, "age" : 30, "gender" : "m", "name" : "Anthony" }, 
+  { "_id" : "9259836/11094844", "_rev" : 11094844, "active" : true, "id" : 101, "age" : 36, "name" : "Fred", "gender" : "m" }, 
+  { "_id" : "9259836/11619132", "_rev" : 11619132, "active" : true, "id" : 108, "age" : 29, "name" : "Jim", "gender" : "m" }, 
+  { "_id" : "9259836/11160380", "_rev" : 11160380, "active" : false, "id" : 102, "age" : 35, "name" : "Jacob", "gender" : "m" } ]
+
+
+/* return a projection from a users collection */
+FOR u IN users 
+  LIMIT 0, 5
+  RETURN { "user" : { "isActive": u.active ? "yes" : "no", "name" : u.name } }
+
+[ { "user" : { "isActive" : "yes", "name" : "John" } }, 
+  { "user" : { "isActive" : "yes", "name" : "Anthony" } }, 
+  { "user" : { "isActive" : "yes", "name" : "Fred" } }, 
+  { "user" : { "isActive" : "yes", "name" : "Jim" } }, 
+  { "user" : { "isActive" : "no", "name" : "Jacob" } } ]
+
+
+/* return a filtered projection from a users collection */
+FOR u IN users 
+  FILTER u.active == true && u.age >= 30
+  SORT u.age DESC
+  RETURN { "age" : u.age, "name" : u.name }
+
+[ { "age" : 37, "name" : "John" }, 
+  { "age" : 37, "name" : "Sophia" }, 
+  { "age" : 36, "name" : "Fred" }, 
+  { "age" : 36, "name" : "Emma" }, 
+  { "age" : 34, "name" : "Madison" }, 
+  { "age" : 33, "name" : "Michael" }, 
+  { "age" : 33, "name" : "Chloe" }, 
+  { "age" : 32, "name" : "Alexander" }, 
+  { "age" : 31, "name" : "Daniel" }, 
+  { "age" : 31, "name" : "Abigail" }, 
+  { "age" : 30, "name" : "Anthony" }, 
+  { "age" : 30, "name" : "Isabella" } ]

Doxygen/Examples.Ahuacatl/aqlexample-grouping

@@ -0,0 +1,45 @@
+/* group users by age */
+FOR u IN users 
+  FILTER u.active == true
+  COLLECT age = u.age INTO group
+  SORT age DESC
+  RETURN { "age" : age, "users" : group }
+
+[ { "age" : 37, "users" : ["Sophia", "John"] }, 
+  { "age" : 36, "users" : ["Emma", "Fred"] }, 
+  { "age" : 34, "users" : ["Madison"] }, 
+  { "age" : 33, "users" : ["Chloe", "Michael"] }, 
+  { "age" : 32, "users" : ["Alexander"] }, 
+  { "age" : 31, "users" : ["Abigail", "Daniel"] }, 
+  { "age" : 30, "users" : ["Isabella", "Anthony"] }, 
+  { "age" : 29, "users" : ["Mary", "Jim"] }, 
+  { "age" : 28, "users" : ["Mariah", "Diego"] } ]
+
+
+/* group users by agegroup and gender */
+FOR u IN users 
+  FILTER u.active == true
+  COLLECT ageGroup = FLOOR(u.age/5) * 5, gender = u.gender INTO group
+  SORT ageGroup DESC
+  RETURN { "ageGroup" : ageGroup, "gender" : gender, "numUsers" : LENGTH(group) }
+
+[ { "ageGroup" : 35, "gender" : "f", "numUsers" : 2 }, 
+  { "ageGroup" : 35, "gender" : "m", "numUsers" : 2 }, 
+  { "ageGroup" : 30, "gender" : "f", "numUsers" : 4 }, 
+  { "ageGroup" : 30, "gender" : "m", "numUsers" : 4 }, 
+  { "ageGroup" : 25, "gender" : "f", "numUsers" : 2 }, 
+  { "ageGroup" : 25, "gender" : "m", "numUsers" : 2 } ]
+
+
+/* get the 3 agegroups with most users */
+FOR u IN users 
+  FILTER u.active == true
+  COLLECT ageGroup = FLOOR(u.age/5) * 5 INTO group
+  FILTER LENGTH(group) > 2 /* group must contain at least 3 users */
+  SORT LENGTH(group) DESC
+  LIMIT 0, 3
+  RETURN { "ageGroup" : ageGroup, "numUsers" : LENGTH(group), "users" : group[*].u.name }
+
+[ { "ageGroup" : 30, "numUsers" : 8, "users" : ["Alexander", "Isabella", "Michael", "Abigail", "Anthony", "Daniel", "Madison", "Chloe"] }, 
+  { "ageGroup" : 25, "numUsers" : 4, "users" : ["Mariah", "Mary", "Jim", "Diego"] }, 
+  { "ageGroup" : 35, "numUsers" : 4, "users" : ["Emma", "Sophia", "Fred", "John"] } ]

Doxygen/Examples.Ahuacatl/aqlexample-join

@@ -0,0 +1,49 @@
+/* getting the names of friends (also users) for users. this is achieved by "joining" a relations table */
+FOR u IN users
+  FILTER u.active == true 
+  LET friends = (FOR f IN userRelations 
+    FILTER f.from == u.id 
+    FOR u2 IN users 
+      FILTER f.to == u2.id 
+      RETURN u2.name
+  ) 
+  RETURN { "user" : u.name, "friends" : friends }
+
+[ { "user" : "John", "friends" : ["Diego", "Mary", "Abigail"] }, 
+  { "user" : "Anthony", "friends" : ["Madison"] }, 
+  { "user" : "Fred", "friends" : ["Mariah"] }, 
+  { "user" : "Jim", "friends" : ["Mariah"] }, 
+  { "user" : "Diego", "friends" : ["Mary"] }, 
+  { "user" : "Sophia", "friends" : ["Madison", "John"] }, 
+  { "user" : "Michael", "friends" : ["John", "Jim"] }, 
+  { "user" : "Emma", "friends" : ["Jacob", "Madison"] }, 
+  { "user" : "Alexander", "friends" : ["Michael", "John"] }, 
+  { "user" : "Daniel", "friends" : ["Eva"] }, 
+  { "user" : "Madison", "friends" : ["Anthony", "Daniel"] }, 
+  { "user" : "Chloe", "friends" : ["Alexander"] }, 
+  { "user" : "Abigail", "friends" : ["Daniel", "John", "Jacob", "Jim"] }, 
+  { "user" : "Isabella", "friends" : ["Madison", "Diego"] }, 
+  { "user" : "Mary", "friends" : ["Isabella", "Diego", "Michael"] }, 
+  { "user" : "Mariah", "friends" : ["Madison", "Ethan", "Eva"] } ]
+
+
+/* getting users favorite song names from a joined "songs" collection */
+FOR u IN users 
+  LET likes = (
+    FOR s IN songs
+      FILTER s._id IN u.likes
+      RETURN CONCAT(s.artist, " - ", s.song)
+  )
+  SORT RAND()
+  LIMIT 0, 8
+  RETURN { "user" : u.name, "likes" : likes }
+
+[ { "user" : "Eva", "likes" : ["Chocolate - Ritmo De La Noche", "4 The Cause - Stand By Me", "Tony Carey - Room with a view"] }, 
+  { "user" : "Mary", "likes" : ["Hall and Oates - Maneater", "Elton John - Candle In The Wind", "A-Ha - Crying In The Rain", "Laid Back - Sunshine Reggae", "Cock Robin - The promise you made"] }, 
+  { "user" : "Alexander", "likes" : ["Moby - Feel so real", "Rednex - Old pop in an oak", "2 Unlimited - No Limit"] }, 
+  { "user" : "Michael", "likes" : ["The Kelly Family - David's Song"] }, 
+  { "user" : "Ethan", "likes" : ["Technotronic - Megamix", "Gipsy Kings - Baila me", "Goombay Dance Band - Seven Tears", "Sandra - Hiroshima"] }, { "user" : "Isabella", "likes" : ["Milli Vanilli - Girl, I'm Gonna Miss You", "Technotronic - Get Up", "Right Said Fred - Don't Talk Just Kiss", "Peter Schilling - Major Tom (Völlig losgelöst)"] }, 
+  { "user" : "Abigail", "likes" : ["Tina Turner - Typical male", "Liquido - Narcotic"] }, 
+  { "user" : "Jim", "likes" : ["Berlin - Take my breath away", "Ashford & Simpson - Solid", "Fine Young Cannibals - She drives me cracy", "Cut'N'Move - Give it up", "Cyndi Lauper - Time after time"] }, 
+  { "user" : "Jacob", "likes" : ["Kylie Minogue - The Loco-motion", "Eruption - Runaway"] } ]
+

Doxygen/Examples.Ahuacatl/aqlexample-simple

@@ -0,0 +1,23 @@
+/* a query that returns a string value. the result string is contained in a list because the result of every valid query is a list */ 
+RETURN "this will be returned"
+
+["this will be returned"]
+
+
+/* a query that creates the cross products of two lists, and runs a projection on it */
+FOR year in [ 2011, 2012, 2013 ]
+  FOR quarter IN [ 1, 2, 3, 4 ]
+    RETURN { "y" : "year", "q" : quarter, "nice" : CONCAT(TOSTRING(quarter), "/", TOSTRING(year)) }
+
+[ { "y" : "year", "q" : 1, "nice" : "1/2011" }, 
+  { "y" : "year", "q" : 2, "nice" : "2/2011" }, 
+  { "y" : "year", "q" : 3, "nice" : "3/2011" }, 
+  { "y" : "year", "q" : 4, "nice" : "4/2011" }, 
+  { "y" : "year", "q" : 1, "nice" : "1/2012" }, 
+  { "y" : "year", "q" : 2, "nice" : "2/2012" }, 
+  { "y" : "year", "q" : 3, "nice" : "3/2012" }, 
+  { "y" : "year", "q" : 4, "nice" : "4/2012" }, 
+  { "y" : "year", "q" : 1, "nice" : "1/2013" }, 
+  { "y" : "year", "q" : 2, "nice" : "2/2013" }, 
+  { "y" : "year", "q" : 3, "nice" : "3/2013" }, 
+  { "y" : "year", "q" : 4, "nice" : "4/2013" } ]

Makefile.files

@@ -407,4 +407,5 @@ WIKI = \
 	UserManual \
 	UserManualBasics \
         Aql \
+        AqlExamples \
 	jsUnity

RestServer/aql-examples.dox

@@ -0,0 +1,56 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief ArangoDB query language (AQL), examples
+///
+/// @file
+///
+/// DISCLAIMER
+///
+/// Copyright 2012 triagens GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+/// @author Copyright 2012, triAGENS GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////////////
+/// @page AqlExamples ArangoDB Query Language (AQL) Examples
+///
+/// This page contains some examples for how to write queries in AQL. For better
+/// understandability, the query results are also included.
+///
+/// @section AqlExamplesSimple Simple queries
+/// 
+/// @verbinclude aqlexample-simple
+/// 
+/// @section AqlExamplesCollection Collection-based queries
+/// 
+/// @verbinclude aqlexample-collection
+/// 
+/// @section AqlExamplesJoins Joins
+/// 
+/// @verbinclude aqlexample-join
+/// 
+/// @section AqlExamplesGrouping Grouping
+/// 
+/// @verbinclude aqlexample-grouping
+/// 
+////////////////////////////////////////////////////////////////////////////////
+
+// Local Variables:
+// mode: c++
+// mode: outline-minor
+// outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @page\\|/// @\\}\\)"
+// End:

RestServer/aql.dox

@@ -106,6 +106,8 @@
 /// to issue read-requests on your database, but modifying data via AQL is
 /// currently not supported.
 ///
+/// For some example queries, please refer to the page @ref AqlExamples.
+///
 /// @section AqlQueryResults Query results
 ///
 /// @subsection AqlQueryResultsSet Result sets

V8/v8-vocbase.cpp

@@ -1033,7 +1033,7 @@ static v8::Handle<v8::Value> ExecuteQueryCursorAhuacatl (TRI_vocbase_t* const vo
   }
 
   if (allowDirectReturn || !result->IsArray()) {
-    // rethrow
+    // return the value we got as it is. this is a performance optimisation
     return scope.Close(result);
   }
 

js/server/ahuacatl.js

@@ -1001,13 +1001,10 @@ function AHUACATL_RELATIONAL_IN (lhs, rhs) {
   if (rightWeight !== AHUACATL_TYPEWEIGHT_LIST) {
     AHUACATL_THROW(internal.errors.ERROR_QUERY_LIST_EXPECTED);
   }
-  
-  var r = AHUACATL_KEYS(rhs, false);
-  var numRight = r.length;
 
+  var numRight = rhs.length;
   for (var i = 0; i < numRight; ++i) {
-    var key = r[i];
-    if (AHUACATL_RELATIONAL_EQUAL(lhs, rhs[key])) {
+    if (AHUACATL_RELATIONAL_EQUAL(lhs, rhs[i])) {
       return true;
     }
   }

js/server/js-ahuacatl.h

@@ -1002,13 +1002,10 @@ static string JS_server_ahuacatl =
   "  if (rightWeight !== AHUACATL_TYPEWEIGHT_LIST) {\n"
   "    AHUACATL_THROW(internal.errors.ERROR_QUERY_LIST_EXPECTED);\n"
   "  }\n"
-  "  \n"
-  "  var r = AHUACATL_KEYS(rhs, false);\n"
-  "  var numRight = r.length;\n"
   "\n"
+  "  var numRight = rhs.length;\n"
   "  for (var i = 0; i < numRight; ++i) {\n"
-  "    var key = r[i];\n"
-  "    if (AHUACATL_RELATIONAL_EQUAL(lhs, rhs[key])) {\n"
+  "    if (AHUACATL_RELATIONAL_EQUAL(lhs, rhs[i])) {\n"
   "      return true;\n"
   "    }\n"
   "  }\n"