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diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/SingleOrErrorProcedure.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/SingleOrErrorProcedure.java
new file mode 100644
index 000000000..15dab764a
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+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/SingleOrErrorProcedure.java
@@ -0,0 +1,85 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.db.common.procedure.single.wrapper;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import org.simantics.db.AsyncReadGraph;
+import org.simantics.db.common.procedure.adapter.AsyncMultiProcedureAdapter;
+import org.simantics.db.common.utils.Logger;
+import org.simantics.db.exception.NoSingleResultException;
+import org.simantics.db.procedure.AsyncProcedure;
+
+final public class SingleOrErrorProcedure<Result> extends AsyncMultiProcedureAdapter<Result> {
+    
+	private Result result = null;
+	final AsyncProcedure<Result> procedure;
+    final AtomicBoolean found = new AtomicBoolean(false);
+    final AtomicBoolean done = new AtomicBoolean(false);
+    
+    public SingleOrErrorProcedure(AsyncProcedure<Result> procedure) {
+        this.procedure = procedure;
+    }
+	
+    @Override
+    public void finished(AsyncReadGraph graph) {
+        
+    	// Shall fire exactly once!
+    	if(done.compareAndSet(false, true)) {
+    		try {
+    			if(result == null) {
+					procedure.exception(graph, new NoSingleResultException("No items " + procedure));
+    			} else {
+        			procedure.execute(graph, result);
+    			}
+    		} catch (Throwable t) {
+        		Logger.defaultLogError(t);
+    		}
+    	}
+        
+    }
+    
+	public void execute(AsyncReadGraph graph, Result result) {
+
+		if(found.compareAndSet(false, true)) {
+			this.result = result;
+		} else {
+			// Shall fire exactly once!
+			if(done.compareAndSet(false, true)) {
+				try {
+					procedure.exception(graph, new NoSingleResultException("Multiple items " + this.result + " and " + result));
+				} catch (Throwable t) {
+		    		Logger.defaultLogError(t);
+				}
+			}
+		}
+
+	}
+
+	public void exception(AsyncReadGraph graph, Throwable t) {
+		// Shall fire exactly once!
+		if(done.compareAndSet(false, true)) {
+			try {
+				procedure.exception(graph, t);
+			} catch (Throwable t2) {
+	    		Logger.defaultLogError(t2);
+			}
+		}
+	}
+    
+    
+    @Override
+    public String toString() {
+        return "SingleOrErrorProcedure -> " + procedure;
+    }
+
+}