Exercise: Error trap when creating temp table

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Category ==> SQL  (115 exercises)
Topic ==> Error-handling  (2 exercises)
Level ==> Relatively easy
Course ==> Advanced SQL
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Create a query to show all the people with really long  names - similar to the following - and run it twice:

SQL exercise - Error-handling (image 1)

You should find that this displays only 3 people

When you run your query a second time, it should crash because the temporary table #BigPeople already exists.  Apply error trapping at the top of the query such that:

  • Your query attempts to delete the table
  • If it already exists, the table is deleted and your query prints out a message saying that this has happened
  • If it didn't already exist, you get a message saying that nothing was deleted

You can test out that this final possibility works by adding the following command at the end of your query:

SQL exercise - Error-handling (image 2)

This command would ensure that the table didn't exist the next time that you run the query

Optionally, save this query as Check deleting temp table.sql, then close it down.

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