7 files declare their use of StatementExecutionStartEvent

DatabaseEventsTest.php in core/tests/Drupal/Tests/Core/Database/DatabaseEventsTest.php
DatabaseEventSubscriber.php in core/modules/system/tests/modules/database_test/src/EventSubscriber/DatabaseEventSubscriber.php
DatabaseEventTest.php in core/tests/Drupal/KernelTests/Core/Database/DatabaseEventTest.php
StatementPrefetch.php in core/lib/Drupal/Core/Database/StatementPrefetch.php
StatementPrefetchIterator.php in core/lib/Drupal/Core/Database/StatementPrefetchIterator.php
StatementWrapper.php in core/lib/Drupal/Core/Database/StatementWrapper.php
StatementWrapperIterator.php in core/lib/Drupal/Core/Database/StatementWrapperIterator.php

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