Merge branch 'devel' of https://github.com/arangodb/arangodb into devel

Documentation/Books/Manual/Administration/Configuration/Wal.mdpp

@@ -30,11 +30,6 @@ not present, it will be created.
 <!-- arangod/Wal/LogfileManager.h -->
 @startDocuBlock WalLogfileAllowOversizeEntries
 
-!SUBSECTION Suppress shape information
-
-<!-- arangod/Wal/LogfileManager.h -->
-@startDocuBlock WalLogfileSuppressShapeInformation
-
 !SUBSECTION Number of reserve logfiles
 
 <!-- arangod/Wal/LogfileManager.h -->

Documentation/Books/Manual/Administration/Durability.mdpp

@@ -58,10 +58,6 @@ logfiles:
 @startDocuBlock WalLogfileAllowOversizeEntries
 
 
-<!-- arangod/Wal/LogfileManager.h -->
-@startDocuBlock WalLogfileSuppressShapeInformation
-
-
 When data gets copied from the write-ahead logfiles into the journals or datafiles
 of collections, files will be created on the collection level. How big these files
 are is determined by the following global configuration value:

Documentation/DocuBlocks/WalLogfileSuppressShapeInformation.md

@@ -1,24 +0,0 @@
-
-@startDocuBlock WalLogfileSuppressShapeInformation
-@brief suppress shape information
-`--wal.suppress-shape-information`
-
-Setting this variable to *true* will lead to no shape information being
-written into the write-ahead logfiles for documents or edges. While this
-is
-a good optimization for a single server to save memory (and disk space),
-it
-it will effectively disable using the write-ahead log as a reliable source
-for replicating changes to other servers. A master server with this option
-set to *true* will not be able to fully reproduce the structure of saved
-documents after a collection has been deleted. In case a replication
-client
-requests a document for which the collection is already deleted, the
-master
-will return an empty document. Note that this only affects replication and
-not normal operation on the master.
-
-**Do not set this variable to *true* on a server that you plan to use as a
-replication master**
-@endDocuBlock
-

arangod/Aql/OptimizerRules.cpp

@@ -3762,6 +3762,8 @@ void arangodb::aql::inlineSubqueriesRule(Optimizer* opt,
     Variable const* out = subqueryNode->outVariable();
     TRI_ASSERT(out != nullptr);
 
+    std::unordered_set<Variable const*> varsUsed;
+
     current = n;
     // now check where the subquery is used
     while (current->hasParent()) {
@@ -3836,6 +3838,7 @@ void arangodb::aql::inlineSubqueriesRule(Optimizer* opt,
           RedundantCalculationsReplacer finder(replacements);
           plan->root()->walk(&finder);
     
+          // abort optimization
           current = nullptr;
         }
       }
@@ -3844,6 +3847,14 @@ void arangodb::aql::inlineSubqueriesRule(Optimizer* opt,
         break;
       }
          
+      varsUsed.clear(); 
+      current->getVariablesUsedHere(varsUsed);
+      if (varsUsed.find(out) != varsUsed.end()) {
+        // we found another node that uses the subquery variable
+        // we need to stop the optimization attempts here
+        break;
+      }
+
       current = current->getFirstParent();
     }
   }

js/server/tests/aql/aql-optimizer-rule-inline-subqueries.js

@@ -226,6 +226,18 @@ function optimizerRuleCollectionTestSuite () {
       var query = "LET x = (FOR doc IN @@cn RETURN doc) FOR doc2 IN x RETURN x";
       var result = AQL_EXPLAIN(query, { "@cn" : cn });
       assertEqual(-1, result.plan.rules.indexOf(ruleName), query); // no optimization
+    },
+
+    testSpecificPlan4 : function () {
+      var query = "LET x = (FOR doc IN @@cn RETURN doc) FOR i IN 1..10 FILTER LENGTH(x) FOR y IN x RETURN y";
+      var result = AQL_EXPLAIN(query, { "@cn" : cn });
+      assertEqual(-1, result.plan.rules.indexOf(ruleName), query); // no optimization
+    },
+
+    testSpecificPlan5 : function () {
+      var query = "FOR j IN 1..10 LET x = (FOR doc IN @@cn RETURN doc) FOR i IN 1..10 FILTER LENGTH(x) FOR y IN x RETURN y";
+      var result = AQL_EXPLAIN(query, { "@cn" : cn });
+      assertEqual(-1, result.plan.rules.indexOf(ruleName), query); // no optimization
     }
 
   };