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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"PreconditionFailed: 412 no matching index found. when using inequality filters","articleBody":"I am using appengine to run my app and gcloud for accessing cloud datastore.\nI have gcloud model where i am storing username and date_time attribute.\n\nbut when i am doing this.\n\n``` python\nfrom gcloud.datastore.query import Query\nfrom datetime import datetime\nquery = Query(kind=\"MyTable\")\nquery.add_filter('username', '=', 'somevalue')\nquery.add_filter('date_time', '\u003c', datetime.now())\n\niterator = query.fetch(limit=10)\nrecords, more, cursor = iterator.next_page()\nprint records\n```\n\nI am getting the following exception.\n\n``` log\n File \"/Users/sathyanarrayanan/Desktop/app/services/cdr_helper.py\", line 528, in fetch_last_users\n    records, more, cursor = iterator.next_page()\n  File \"/Users/sathyanarrayanan/Desktop/app/gcloud/datastore/query.py\", line 388, in next_page\n    transaction_id=transaction and transaction.id,\n  File \"/Users/sathyanarrayanan/Desktop/app/gcloud/datastore/connection.py\", line 257, in run_query\n    datastore_pb.RunQueryResponse)\n  File \"/Users/sathyanarrayanan/Desktop/app/gcloud/datastore/connection.py\", line 108, in _rpc\n    data=request_pb.SerializeToString())\n  File \"/Users/sathyanarrayanan/Desktop/app/gcloud/datastore/connection.py\", line 85, in _request\n    raise make_exception(headers, content, use_json=False)\nPreconditionFailed: 412 no matching index found.\n```\n\nBelow is my index file.\n\n``` yaml\n#File index.yaml\n\n- kind: MyTable\n  ancestor: yes\n  properties:\n  - name: date_time\n\n- kind: MyTable\n  ancestor: yes\n  properties:\n  - name: date_time\n    direction: desc\n\n- kind: MyTable\n  ancestor: yes\n  properties:\n  - name: username\n    direction: asc\n  - name: date_time\n    direction: desc\n\n- kind: MyTable\n  ancestor: yes\n  properties:\n  - name: username\n    direction: asc\n  - name: date_time\n```\n\nfor more details: http://stackoverflow.com/questions/32607351/412-no-matching-index-found-while-executing-a-query-in-cloud-datastore\n","author":{"url":"https://github.com/sourcepirate","@type":"Person","name":"sourcepirate"},"datePublished":"2015-09-18T06:26:44.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/1143/google-cloud-python/issues/1143"}