Without an ORDER BY clause, the order of rows returned by a SELECT is

Question

Accepted Answer

B. not guaranteed; may differ each run

SQL is built on the relational model, where a relation is an unordered set.
The DBMS is free to return rows in whatever order is most efficient (which can change as the data grows or the optimiser picks a different plan).
To get a predictable order you must say so with ORDER BY.

Answer

always ascending by primary key

Answer

always insertion order, oldest row first

Answer

always alphabetical on the first column

Without an ORDER BY clause, the order of rows returned by a SELECT is

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