In Apex, an exception that is not caught bubbles up the stack. For database work, DmlException is common — catch the specific type when you can, keep finally for cleanup that must run either way.

try {
    update accounts;
} catch (DmlException e) {
    // not taken in this scenario
    System.debug(LoggingLevel.ERROR, e.getMessage());
} catch (Exception e) {
    // …
} finally {
    // always runs: good place for limits-neutral cleanup notes
}

Reading the path: try completes → finally runs → code after the block runs.

Strings from the database or UI are often null, empty, or only spaces. In Apex, == null checks only null; String.isBlank covers null, empty, and whitespace — pick the guard that matches your business rule.

String name = record.Name; // might be null
if (String.isBlank(name)) {
    name = 'Unnamed';   // safe default before DML or SOQL
}