diff --git a/src/sonic-yang-mgmt/tests/yang-model-tests/custom_code/cropConfigDB.py b/src/sonic-yang-mgmt/tests/yang-model-tests/custom_code/cropConfigDB.py
new file mode 100644
index 00000000000..2d484757136
--- /dev/null
+++ b/src/sonic-yang-mgmt/tests/yang-model-tests/custom_code/cropConfigDB.py
@@ -0,0 +1,133 @@
+# This script is used to
+
+import yang as ly
+
+from json import dump, load, dumps, loads
+from xmltodict import parse
+from os import listdir, walk, path
+from os.path import isfile, join, splitext
+
+# Read given JSON file
+def readJsonFile(fileName):
+    #print(fileName)
+    try:
+        with open(fileName) as f:
+            result = load(f)
+    except Exception as e:
+        raise Exception(e)
+
+    return result
+
+class sonic_yang:
+
+    def __init__(self, yangDir):
+        self.yangDir = yangDir
+        self.ctx = None;
+        self.yangFiles = list()
+        self.confDbYangMap = dict()
+        self.yJson = list()
+
+        return
+
+    """
+        load all YANG models before test run
+    """
+    def loadYangModel(self):
+
+        yangDir = self.yangDir
+        # get all files
+        yangFiles = [f for f in listdir(yangDir) if isfile(join(yangDir, f))]
+        # get all yang files
+        yangFiles = [f for f in yangFiles if splitext(f)[-1].lower()==".yang"]
+        yangFiles = [f.split('.')[0] for f in yangFiles]
+        # load yang mdoules
+        self.ctx = ly.Context(yangDir)
+        self.yangFiles = yangFiles
+        print(yangFiles)
+        for f in yangFiles:
+            # load a module
+            m = self.ctx.get_module(f)
+            if m is not None:
+                print("module already exist: {}".format(m.name()))
+            else:
+                m = self.ctx.load_module(f)
+                if m is not None:
+                    print("module: {} is loaded successfully".format(m.name()))
+                else:
+                    print("module not loaded correctly: {}".format(m.name()))
+                    return
+
+        return
+
+    """
+        load JSON schema format from yang models
+    """
+    def loadJsonYangModels(self):
+
+        for f in self.yangFiles:
+            m = self.ctx.get_module(f)
+            if m is not None:
+                xml = m.print_mem(ly.LYD_JSON, ly.LYP_FORMAT)
+                self.yJson.append(parse(xml))
+
+        return
+
+    """
+        Create a map from config DB tables to
+    """
+    def createDBTableToModuleMap(self):
+
+        for j in self.yJson:
+            # get module name
+            moduleName = j['module']['@name']
+            if "sonic-head" in moduleName or "sonic-common" in moduleName:
+                continue;
+            # get all top level container
+            topLevelContainer = j['module']['container']
+            if topLevelContainer is None:
+                raise Exception("topLevelContainer not found")
+
+            assert topLevelContainer['@name'] == moduleName
+
+            container = topLevelContainer['container']
+            # container is a list
+            if isinstance(container, list):
+                for c in container:
+                    self.confDbYangMap[c['@name']] = \
+                        "/"+moduleName+":"+topLevelContainer['@name']+"/"+c['@name']
+            # container is a dict
+            else:
+                self.confDbYangMap[container['@name']] = \
+                    "/"+moduleName+":"+topLevelContainer['@name']+"/"+container['@name']
+
+        return
+
+    """
+        Read config file and crop it as per yang models
+    """
+    def cropConfigDB(self, configFile, croppedFile):
+
+        jIn = readJsonFile(configFile)
+        for table in jIn.keys():
+            if table not in self.confDbYangMap:
+                del jIn[table]
+
+        with open(croppedFile, 'w') as f:
+            dump(jIn, f, indent=2)
+
+        return
+
+# end of class
+
+def main():
+    configFile = "sample_config_db.json"
+    croppedFile = "cropped_" + configFile
+
+    sy = sonic_yang("../../../yang-models")
+    sy.loadYangModel()
+    sy.loadJsonYangModels()
+    sy.createDBTableToModuleMap()
+    sy.cropConfigDB(configFile, croppedFile)
+
+if __name__ == "__main__":
+    main()