how to avoid inserting duplicated rows working on pandas dataframe?
<p>I am working on pandas dataframe and mysql, my table is timeseries related like,</p>

<pre><code>symbol_id  date     close
1          2016-6-1 123
1          2016-6-2 133
1          2016-6-3 143
2          2016-6-1 23
2          2016-6-2 33
2          2016-6-3 43
</code></pre>

<p>When asserting a new dataframe into the table, I use </p>

<pre><code>df.to_sql(name='symbol_test1', con=engine, if_exists = 'replace', index=True)
</code></pre>