Remove white space within string using awk or sed
<p>Given input file:</p>

<pre><code>col1 as 'prod 1', col3 as 'prod 2', col9 as 'prod type 2'
</code></pre>

<p>Need to remove quote and replace blank space within quote by _ . Can we do it by awk or sed?</p>

<p>Desired output:</p>

<pre><code>col1 as prod_1, col3 as prod_2, col9 as prod_type_2
</code></pre>