What Happens to Database Query Order When 'Order By' is Omitted?

Result sorting after omitting "Order By" in database query

In database queries, the "Order By" clause is used to specify the criteria for sorting results. But what happens if this clause is omitted?

Unspecified sorting: a confusing problem

In the past, many people believed that queries without an explicitly defined "Order By" clause would default to ordering results based on the items listed in the "Where" clause. However, this is not the case.

Arbitrary and unpredictable ordering

Without the "Order By" specification, the database will have no predefined collation. Therefore, the results will be returned in any chosen order. This ordering may even differ every time the same query is executed.

There is no "natural order" in relational databases

Contrary to popular belief, there is no inherent "natural order" to data in a relational database. The only way to ensure consistent ordering is to explicitly specify the sorting criteria using the "Order By" clause.

Conclusion: For reliable results, specify "Order By"

It must be remembered that without the "Order By" clause, the database query has no defined ordering. For predictable and reliable results, be sure to explicitly specify the desired sorting criteria using the "Order By" clause.

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