Sorting Information

At the beginning of this chapter, we said that the SELECT operation can be broken down into three smaller operations: the SELECT statement, the SELECT expression, and the SELECT query. We also stated that you can combine these operations in various ways to answer complex requests. However, you also need to combine these operations in order to sort the rows of a result set.

By definition, the rows of a result set returned by a SELECT statement are unordered. The sequence in which they appear is typically based on their physical position in the table. (The actual sequence is often determined dynamically by your database system based on how it decides to most efficiently satisfy your request.) The only way to sort the result ...

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