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I don't understand. &nbsp;What result are you looking for? &nbsp;I'm not sure you can do a JOIN on NULL data.
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I don't understand.  What result are you looking for?  I'm not sure you can do a JOIN on NULL data.

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I am downloading better descriptions directly from a distributor (that are not provided in the product feed). &nbsp;<br />
<br />
If my PHP script or the distributor's website times the script out, I want to start again where it quit.<br />
<br />
Thanks for your help!
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I am downloading better descriptions directly from a distributor (that are not provided in the product feed).  

If my PHP script or the distributor's website times the script out, I want to start again where it quit.

Thanks for your help!

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I appreciate the help!! &nbsp;That worked perfect!!
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I appreciate the help!!  That worked perfect!!

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I have indexed the SKU column in both DB tables. &nbsp;How do I speed this query up? &nbsp; (There are 20,000+ records in table &quot;Download&quot;)<br />
<br />
I was using WHERE NOT IN and thought I could speed it up some &nbsp;by using a LEFT JOIN and IS NULL.<br />
<br />
Thanks for your help!!<br />
<br />

<pre><code id="code-10-29017312-1">$query1 = $conn-&gt;query('SELECT DISTINCT `Download`.SKU FROM `Download` LEFT JOIN MissingDescriptions ON `Download`.SKU = MissingDescriptions.SKU WHERE MissingDescriptions.SKU IS NULL');</code></pre>
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I have indexed the SKU column in both DB tables.  How do I speed this query up?   (There are 20,000+ records in table "Download")

I was using WHERE NOT IN and thought I could speed it up some  by using a LEFT JOIN and IS NULL.

Thanks for your help!!

(CODE)

How do I speed up this PDO query

PHP is a widely-used server-side scripting language especially suited for web development, powering tens of millions of sites from Facebook to personal WordPress blogs. PHP is often paired with the MySQL relational database, but includes support for most other mainstream databases. By utilizing different Server APIs, PHP can work on many different web servers as a server-side scripting language.

SQL (Structured Query Language) is designed to be used in conjunction with relational database products as of a means of working with sets of data. SQL consists of data definition, data manipulation, and procedural elements. Its scope includes data insert, query, update and delete, schema creation and modification, and data access control.