diff --git a/bin/db_assembler/db_assembler.sh b/bin/db_assembler/db_assembler.sh
index 6993c8efa..1716b71eb 100755
--- a/bin/db_assembler/db_assembler.sh
+++ b/bin/db_assembler/db_assembler.sh
@@ -8,142 +8,142 @@ if [ -f "./config.sh"  ]; then
     source "./config.sh" # should overwrite previous
 fi
 
-version_marker="$OUTPUT_FOLDER/ZZZ_latest_version_"
-
-version="0000_00_00_00"
-for entry in "$version_marker"*
-do
-    if [ -f "$entry" ]; then
-        version=${entry#$version_marker}
-    fi
-
-    break
-done
-
-#
-# You can pass latest version as first argument of this script
-#
-if [ -z "$1" ]; then
-	read -p "Enter latest sql version ( leave blank to use : $version )" $rev
-	version=${rev:-$version}
+unamestr=`uname`
+if [[ "$unamestr" == 'Darwin' ]]; then
+    MD5_CMD="md5"
 else
-	version=$1
+    MD5_CMD="md5sum"
 fi
 
+reg_file="$OUTPUT_FOLDER/.zzz_db_assembler_registry.sh"
+
+declare -A registry
+
+if [ -f "$reg_file" ]; then
+    source "$reg_file"
+fi
 
 echo "===== STARTING PROCESS ====="
 
-gtversion=""
 
 function assemble() {
-	database=$1
-	start_sql=$2
+    database=$1
+    start_sql=$2
 
-	var_base="DB_"$database"_PATHS"
-	base=${!var_base}
+    var_base="DB_"$database"_PATHS"
+    base=${!var_base}
 
-	var_updates="DB_"$database"_UPDATE_PATHS"
-	updates=${!var_updates}
+    var_updates="DB_"$database"_UPDATE_PATHS"
+    updates=${!var_updates}
 
-	var_custom="DB_"$database"_CUSTOM_PATHS"
-	custom=${!var_custom}
+    var_custom="DB_"$database"_CUSTOM_PATHS"
+    custom=${!var_custom}
 
 
-	suffix_base=""
-	suffix_upd=""
-	suffix_custom=""
+    suffix_base=""
+    suffix_upd=""
+    suffix_custom=""
 
-	if (( $ALL_IN_ONE == 0 )); then
-		suffix_base="_base"
-	fi;
+    if (( $ALL_IN_ONE == 0 )); then
+        suffix_base="_base"
+    fi;
 
-	echo "" > $OUTPUT_FOLDER$database$suffix_base".sql"
+    echo "" > $OUTPUT_FOLDER$database$suffix_base".sql"
 
 
-	if [ ! ${#base[@]} -eq 0 ]; then
-		echo "Generating $OUTPUT_FOLDER$database$suffix_base ..."
+    if [ ! ${#base[@]} -eq 0 ]; then
+        echo "Generating $OUTPUT_FOLDER$database$suffix_base ..."
 
-		for d in "${base[@]}"
-	 	do
-			if [ ! -z $d ]; then
-				for entry in "$d"/*.sql "$d"/**/*.sql
-				do
-					if [ -e $entry ]; then 
-			  			cat "$entry" >> $OUTPUT_FOLDER$database$suffix_base".sql"
-					fi
-				done
-			fi
-		done
-	fi
+        for d in "${base[@]}"
+        do
+            if [ ! -z $d ]; then
+                for entry in "$d"/*.sql "$d"/**/*.sql
+                do
+                    if [[ -e $entry ]]; then
+                        cat "$entry" >> $OUTPUT_FOLDER$database$suffix_base".sql"
+                    fi
+                done
+            fi
+        done
+    fi
 
-	if (( $ALL_IN_ONE == 0 )); then
-		suffix_upd="_updates"
+    if (( $ALL_IN_ONE == 0 )); then
+        suffix_upd="_updates"
 
-		echo "" > $OUTPUT_FOLDER$database$suffix_upd".sql"
-	fi;
+        echo "" > $OUTPUT_FOLDER$database$suffix_upd".sql"
+    fi;
 
-	if [ ! ${#updates[@]} -eq 0 ]; then
-		echo "Generating $OUTPUT_FOLDER$database$suffix_upd ..."
+    if [ ! ${#updates[@]} -eq 0 ]; then
+        echo "Generating $OUTPUT_FOLDER$database$suffix_upd ..."
 
-		for d in "${updates[@]}"
-	 	do
-			for entry in "$d"/*.sql "$d"/**/*.sql
-			do
-			  if [ ! -z $d ]; then
-				  file=$(basename $entry)
-				  if [[ "$file" > "$start_sql" ]]
-				  then
-					if [ -e $entry ]; then 
-						if [[ "$gtversion" < "$file" ]]; then
-							gtversion=$file
-						fi
+        for d in "${updates[@]}"
+        do
+            if [ ! -z $d ]; then
+                for entry in "$d"/*.sql "$d"/**/*.sql
+                do
+                    if [[ ! -e $entry ]]; then
+                        continue
+                    fi
 
-				  		cat "$entry" >> $OUTPUT_FOLDER$database$suffix_upd".sql"
-					fi
-				  fi
-			  fi
-			done
-		done
-	fi
+                    file=$(basename "$entry")
+                    hash=$($MD5_CMD "$entry")
+                    hash="${hash%% *}" #remove file path
+                    if [[ -z ${registry[$hash]} ]]; then
+                        registry["$hash"]="$file"
+                        echo "-- New update sql: "$file
+                        cat "$entry" >> $OUTPUT_FOLDER$database$suffix_upd".sql"
+                    fi
+                done
+            fi
+        done
+    fi
 
-	if (( $ALL_IN_ONE == 0 )); then
-		suffix_custom="_custom"
+    if (( $ALL_IN_ONE == 0 )); then
+        suffix_custom="_custom"
 
-		echo "" > $OUTPUT_FOLDER$database$suffix_custom".sql"
-	fi;
+        echo "" > $OUTPUT_FOLDER$database$suffix_custom".sql"
+    fi;
 
-	
 
-	if [ ! ${#custom[@]} -eq 0 ]; then
-		echo "Generating $OUTPUT_FOLDER$database$suffix_custom ..."
 
-		for d in "${custom[@]}"
-	 	do
-			if [ ! -z $d ]; then
-				for entry in "$d"/*.sql "$d"/**/*.sql
-				do
-					if [ -e $entry ]; then 
-			  			cat "$entry" >> $OUTPUT_FOLDER$database$suffix_custom".sql"
-					fi
-				done
-			fi
-		done
-	fi
+    if [ ! ${#custom[@]} -eq 0 ]; then
+        echo "Generating $OUTPUT_FOLDER$database$suffix_custom ..."
+
+        for d in "${custom[@]}"
+        do
+            if [ ! -z $d ]; then
+                for entry in "$d"/*.sql "$d"/**/*.sql
+                do
+                    if [[ ! -e $entry ]]; then
+                        continue
+                    fi
+
+                    file=$(basename "$entry")
+                    hash=$($MD5_CMD "$entry")
+                    hash="${hash%% *}" #remove file path
+                    if [[ -z ${registry[$hash]} ]]; then
+                        registry["$hash"]="$file"
+                        echo "-- New custom sql: "$file
+                        cat "$entry" >> $OUTPUT_FOLDER$database$suffix_custom".sql"
+                    fi
+                done
+            fi
+        done
+    fi
 }
 
 mkdir -p $OUTPUT_FOLDER
 
 for db in ${DATABASES[@]}
 do
-	assemble "$db" $version".sql"
+    assemble "$db" $version".sql"
 done
 
-if [ ! -z $gtversion ]; then
-    if [ -f $version_marker* ]; then
-        rm $version_marker*
-    fi
-    echo $gtversion > $OUTPUT_FOLDER"ZZZ_latest_version_"${gtversion%.*}
-fi
+echo "" > $reg_file
+
+for i in "${!registry[@]}"
+do
+  echo "registry['"$i"']='"${registry[$i]}"'" >> "$reg_file"
+done
 
 echo "===== DONE ====="
-