Some code clarifications.

neo4j · Dec 4, 2017 · a543c4b · a543c4b
1 parent f37b84f
commit a543c4b
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Showing 3 changed files with 13 additions and 2 deletions.
diff --git a/community/kernel/src/main/java/org/neo4j/kernel/impl/newapi/AllStoreHolder.java b/community/kernel/src/main/java/org/neo4j/kernel/impl/newapi/AllStoreHolder.java
@@ -265,6 +265,8 @@ void relationship( RelationshipRecord record, long reference, PageCursor pageCur
     @Override
     void property( PropertyRecord record, long reference, PageCursor pageCursor )
     {
+        //We need to load forcefully here since otherwise we can have inconsistent reads
+        //for properties across blocks, see org.neo4j.graphdb.ConsistentPropertyReadsIT
         properties.loadRecordByCursor( reference, record, RecordLoad.FORCE, pageCursor );
     }
 

diff --git a/community/kernel/src/main/java/org/neo4j/kernel/impl/newapi/NodeCursor.java b/community/kernel/src/main/java/org/neo4j/kernel/impl/newapi/NodeCursor.java
@@ -76,6 +76,7 @@ void single( long reference, Read read )
             pageCursor = read.nodePage( reference );
         }
         this.next = reference;
+        //This marks the cursor as a "single cursor"
         this.highMark = NO_ID;
         this.read = read;
         this.labelCursor = read.labelCursor();
@@ -229,14 +230,15 @@ else if ( hasChanges && txs.nodeIsDeletedInThisTx( next ) )
             }
             if ( next > highMark )
             {
-                if ( highMark == NO_ID )
+                if ( isSingle() )
                 {
-                    //we are using single
+                    //we are a "single cursor"
                     next = NO_ID;
                     return inUse();
                 }
                 else
                 {
+                    //we are a "scan cursor"
                     //Check if there is a new high mark
                     highMark = read.nodeHighMark();
                     if ( next > highMark )
@@ -288,4 +290,9 @@ private void reset()
         next = NO_ID;
         setId( NO_ID );
     }
+
+    private boolean isSingle()
+    {
+        return highMark == NO_ID;
+    }
 }
diff --git a/.../src/main/java/org/neo4j/kernel/impl/storageengine/impl/recordstorage/StoreStatement.java b/.../src/main/java/org/neo4j/kernel/impl/storageengine/impl/recordstorage/StoreStatement.java
@@ -465,6 +465,8 @@ private static ByteBuffer readDynamic( AbstractDynamicStore store, long referenc
         DynamicRecord record = store.newRecord();
         do
         {
+            //We need to load forcefully here since otherwise we can have inconsistent reads
+            //for properties across blocks, see org.neo4j.graphdb.ConsistentPropertyReadsIT
             store.getRecordByCursor( reference, record, RecordLoad.FORCE, page );
             reference = record.getNextBlock();
             byte[] data = record.getData();