Title: Solr 8.0.0 Delta import Issue
Tags: solr
Question: The delta import is not working. No new records get indexed. posting_id is a unique id for each record.

```<dataConfig&gt;
<dataSource type="JdbcDataSource"
            driver="com.mysql.jdbc.Driver"
            batchSize="-1"
            autoReconnect="true"
            socketTimeout="0"
            connectTimeout="0"
            encoding="UTF-8"
            url="jdbc:mysql://xxx.xxx.xxx.xx:3306/news?zeroDateTimeBehavior=convertToNull"
            user="admin"
            password="admin"/&gt;
<document&gt;
<!--<entity name="news10" query="select * from news10"
            deltaQuery="select posting_id from item where last_modified &gt; '${dataimporter.last_index_time}'"&gt; 
</entity&gt;--&gt;
<entity name="news10" pk="posting_id"
  query="SELECT * FROM news10"
  deltaImportQuery="SELECT * FROM news10
    WHERE posting_id = '${dataimporter.delta.posting_id}'"
  deltaQuery="SELECT posting_id FROM news10
    WHERE last_modified &gt; '${dataimporter.last_index_time}'"&gt;
</entity&gt;
</document&gt;
</dataConfig&gt;
```

Comment: https://stackoverflow.com/questions/21580331/solr-delta-import-not-working

Comment: https://stackoverflow.com/questions/31110290/solr-delta-import-does-not-working-but-full-import-working-fine



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