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Doing a GROUP BY Statement

Doing a GROUP BY Statement

Question:
How do I do a “group by” SQL statement? I want to return all rows and columns with ** records. Here is the data sample:

columnA columnB columnCAAA      2334   jan/01/99 **AAA         4   mar/05/99 BBB        32   feb/20/99 BBB         3   feb/23/99BBB        32   feb/24/99 **CCC     32439   jan/23/99 **DDD       666   may/01/99 EEE       444   mar/03/99 **

Conditions:

  • SELECT columnA columnB columnC
  • GROUP BY ColumnA
  • columnC <= mar/04/99 and the max row, which is in the same group

Answer:
What’s required is to treat this problem in two passes.

First isolate the records that are the case by selecting the max of Column B grouped by Column A. That will at least get you the highest value for the group.

Next, you need another pass to eliminate the outlying dates.

Sorry this solution isn’t more elegant.

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