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POSubqueries yielding more results then expected on join of two subsets
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10239581
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2012-04-20T02:47:22.803
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2012-04-20T17:21:09.757
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2012-04-20T17:21:09.757
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I'm receiving more ID's then possible after performing a left outer join statement on two tables. Context: I've narrowed down two tables from larger data sets. Below are the queries found I've used to obtain IDs possible after selecting from the larger data set. I am trying to JOIN two data sets together based upon the personID. I am preforming a LEFT JOIN because I want to retain all data in the smallerset table while pairing it with data from narrowed data table. Upon running this query on a subset of a larger data set I receive the following IDs: <pre><code>select s.personID from st.smallerset as s; 41486 41490 41493 41496 ... </code></pre> Now, upon running the second query, I receive the following: <pre><code>select r.* from st.secondlargedataset as r, st.condition as h where r.personID=h.personID group by r.personID; </code></pre> I receive the following queries: <pre><code>41544 41577 41595 41605 ... </code></pre> So far, so good. Everything is as expected. However, when I run this next subquery as I try to join these two subsets I get unexpected results. <pre><code>select s.personID from st.smallerset as s left join (select r.* from st.secondlargedataset as r, st.condition as h where r.personID=h.personID group by r.personID) as v on s.personID=v.personID; 41485 41486 41489 41490 41493 41496 41510 41512 41513 41516 </code></pre> Included in this result is data that is not include in either prior query. Specifically IDs <code>41485</code>, <code>41489</code>, <code>41496</code> et cetera. I'm clueless as to why these IDs are appearing since when I break the queries into separate queries I get the IDs I need.
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<sql><dataset><left-join><sas><proc-sql>
Title
Subqueries yielding more results then expected on join of two subsets
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