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POSQL query with three different tables with distinct
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  1. POSQL query with three different tables with distinct
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    copied!<p>I'm having some trouble with a SQL query across 3 tables with different attributes. Here are the tables and the attributes that I'd like to query in each of them:</p> <blockquote> <p>news_stories - time, headline</p> <p>per_minute_quotes - security_id, timestamp, last_price</p> <p>securities - name, id_bb, id</p> </blockquote> <p>What I'd like to do is retrieve a security name, id from the securities table, find headlines that correspond to that security (with a timestamp) from the *news_stories* table and find the last_price for that security at the same time as the article from the per_minute_quotes table. </p> <p>Does this make sense? Please see what I've managed to do so far below... </p> <pre><code>SELECT DISTINCT `news_stories`.`time` , `securities`.`name` , `adjusted_daily_quotes`.`security_id` , `news_stories`.`headline` , `securities`.`id_bb` , `securities`.`id` FROM `schema`.`adjusted_daily_quotes` , `schema`.`securities` , `schema`.`news_stories` WHERE ( (`adjusted_daily_quotes`.`security_id`) = '498' AND (`securities`.`id`) = '498' AND (`securities`.`id_bb`) LIKE '267%' AND (`news_stories`.`headline`) LIKE '%:267') LIMIT 0,50; </code></pre> <p>This will basically do the first part of my query, ie. it isn't connected with the last_price. Here is my attempt at doing that:</p> <pre><code>SELECT DISTINCT `news_stories`.`time` , `securities`.`name` , `per_minute_quotes`.`security_id` , `news_stories`.`headline` , `securities`.`id_bb` , `securities`.`id` , `per_minute_quotes`.`timestamp` , `per_minute_quotes`.`last_price` FROM `schema`.`per_minute_quotes` , `schema`.`securities` , `schema`.`news_stories` WHERE ( (`per_minute_quotes`.`security_id`) = '498' AND (`securities`.`id`) = '498' AND (`securities`.`id_bb`) LIKE '267%' AND (`news_stories`.`headline`) LIKE '%:267 HK' AND (`per_minute_quotes`.`timestamp`) &lt;= (`news_stories`.`time`)) LIMIT 0,5; </code></pre> <p>However, this query returns 5 of the same headline for some reason, all with the same time. I would really appreciate help with forming this query. Does that have something to do with the DISTINCT operator? I've tried using GROUP BY but with no luck.</p> <p>Thanks in advance!</p>
 

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