Implemented Eager Loading for samplingfeaturedataset query.

Author: Elijahwalkerwest

odm2api/ODM2/services/readService.py

@@ -37,6 +37,7 @@
 import pandas as pd
 
 from sqlalchemy import distinct, exists
+from sqlalchemy.orm import lazyload, joinedload, contains_eager, eagerload, defer, deferred, subqueryload
 
 __author__ = 'sreeder'
 
@@ -78,7 +79,6 @@ class SamplingFeatureDataSet():
     def __init__(self, samplingfeature, datasetresults, relatedfeatures):
         sf = samplingfeature
 
-        self.SamplingFeature = sf
         self.SamplingFeatureID = sf.SamplingFeatureID
         self.SamplingFeatureUUID = sf.SamplingFeatureUUID
         self.SamplingFeatureTypeCV = sf.SamplingFeatureTypeCV
@@ -955,10 +955,24 @@ def getSamplingFeatureDatasets(self, ids=None, codes=None, uuids=None, dstype=No
             sfds=[]
             for sf in sf_list:
 
-                q = self._session.query(DataSetsResults)\
-                    .join(Results)\
-                    .join(FeatureActions)\
-                    .filter(FeatureActions.SamplingFeatureID == sf.SamplingFeatureID)
+                # q = self._session.query(DataSetsResults)\
+                #     .options(subqueryload(DataSetsResults.ResultObj)\
+                #              .subqueryload(Results.FeatureActionObj)\
+                #              .load_only(FeatureActions.SamplingFeatureID))\
+                #     .filter(FeatureActions.SamplingFeatureID == sf.SamplingFeatureID)
+
+                q = self._session.query(DataSetsResults) \
+                    .join(DataSetsResults.ResultObj)\
+                    .join(Results.FeatureActionObj)\
+                    .filter(FeatureActions.SamplingFeatureID == sf.SamplingFeatureID)\
+                    .options(contains_eager(DataSetsResults.ResultObj).contains_eager(Results.FeatureActionObj)\
+                    .load_only(FeatureActions.SamplingFeatureID))
+
+                # q = self._session.query(DataSetsResults)\
+                # .join(Results)\
+                # .join(FeatureActions)\
+                # .filter(FeatureActions.SamplingFeatureID == sf.SamplingFeatureID)
+
 
                 if dstype:
                     q = q.filter_by(DatasetTypeCV=dstype)