What is the sequence of executing Oracle when using case conditions in SQL core?

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The sequence of executing Oracle when using case conditions in SQL core is as follows:

1. The SQL engine evaluates the expression or column being checked in the case statement.
2. It then compares the value of the expression or column with the values in the when clauses in the order they are written in the statement.
3. If a match is found, the SQL engine executes the expressions in the corresponding then clause.
4. If no match is found, the SQL engine will execute the else clause if it is present.
5. If no matching when clause or else clause is found, the SQL engine will return a null value.