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POMySQL join query with only one record from joined table, ordered by date
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2013-08-09T10:03:15.390
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I have two tables in MySQL I want to join in one query. Table one opc_tag: <pre><code>id name </code></pre> Table two opc_data: <pre><code>id tag_id value created_at </code></pre> I want to list all rows from opc_tag with the last record from opc_data based on the "created_at" field. I've tried to find it on Google, but it does not work. The following query selected the tags with multiple records from opc_data-table. <pre><code>SELECT t.*, d.* FROM opc_tag t LEFT JOIN opc_data d ON t.id = d.tag_id WHERE d.created_at = ( SELECT MAX(d.created_at) FROM opc_data d2 WHERE d2.tag_id = t.id ) </code></pre>
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<mysql><sql>
Title
MySQL join query with only one record from joined table, ordered by date
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1. COHello and welcome to stackoverflow. As your issue is probably not as simple as we might think at first, you should perhaps edit your question to show an *example* of actual input data and the *expected* output. Once done, while waiting for answers you should take a look on our help: http://stackoverflow.com/help/someone-answers
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 USSylvain Leroux

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