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sorting - SQL: ORDER BY using a substring within a specific column... possible?

I have a database whose columns are npID, title, URL, and issue.

Here is an example of two years' entries:

npID               title               URL               issue
88                 EMR Newsletter      a.com             2010 Third_Quarter
89                 EMR Newsletter      b.com             2010 Second_Quarter
43                 EMR Newsletter      c.com             2010 First_Quarter
47                 EMR Newsletter      d.com             2009 Winter
45                 EMR Newsletter      e.com             2009 Summer
46                 EMR Newsletter      f.com             2009 Spring
44                 EMR Newsletter      g.com             2009 Fall

What I would like to do is be able to sort the results based on substrings within the "issue" column. However, until 2010, the client used seasons as the header and in 2010, they started using quarters. Is there a way in the "ORDER BY" I can provide a list of words to sort by if/when they're found anywhere in the "issue" value?

I would like the end result to be something like this:

npID               title               URL               issue
43                 EMR Newsletter      c.com             2010 First_Quarter
89                 EMR Newsletter      b.com             2010 Second_Quarter
88                 EMR Newsletter      a.com             2010 Third_Quarter
47                 EMR Newsletter      d.com             2009 Winter
45                 EMR Newsletter      e.com             2009 Summer
46                 EMR Newsletter      f.com             2009 Spring
44                 EMR Newsletter      g.com             2009 Fall
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1 Answer

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You can put a CASE statement in the ORDER BY to accomplish this. A better route would be to change the application and table to actually store this relevant data in columns where it belongs when you have the development time to do that.

ORDER BY
    CAST(SUBSTRING(issue, 1, 4) AS INT) DESC,  -- Year
    CASE
        WHEN issue LIKE '%First_Quarter' OR issue LIKE '%Winter' THEN 1
        WHEN issue LIKE '%Second_Quarter' OR issue LIKE '%Spring' THEN 2
        WHEN issue LIKE '%Third_Quarter' OR issue LIKE '%Summer' THEN 3
        WHEN issue LIKE '%Fourth_Quarter' OR issue LIKE '%Fall' THEN 4
    END

Order the seasons however you want. You could also order them in a specific way (Q1 followed by Spring, followed by Q2, etc.) by adjusting the CASE statement.


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