24 files declare their use of DatabaseException

BatchStorage.php in core/lib/Drupal/Core/Batch/BatchStorage.php
DatabaseBackend.php in core/lib/Drupal/Core/Flood/DatabaseBackend.php
DatabaseBackend.php in core/lib/Drupal/Core/Cache/DatabaseBackend.php
DatabaseCacheTagsChecksum.php in core/lib/Drupal/Core/Cache/DatabaseCacheTagsChecksum.php
DatabaseLockBackend.php in core/lib/Drupal/Core/Lock/DatabaseLockBackend.php
DatabaseQueue.php in core/lib/Drupal/Core/Queue/DatabaseQueue.php
DatabaseStorage.php in core/lib/Drupal/Core/KeyValueStore/DatabaseStorage.php
DatabaseStorage.php in core/lib/Drupal/Core/Config/DatabaseStorage.php
DbLog.php in core/modules/dblog/src/Logger/DbLog.php
EventException.php in core/lib/Drupal/Core/Database/Exception/EventException.php
FieldsOverlapException.php in core/lib/Drupal/Core/Database/Query/FieldsOverlapException.php
InstallerRedirectTrait.php in core/lib/Drupal/Core/Installer/InstallerRedirectTrait.php
InvalidMergeQueryException.php in core/lib/Drupal/Core/Database/Query/InvalidMergeQueryException.php
LargeQueryTest.php in core/modules/mysql/tests/src/Kernel/mysql/LargeQueryTest.php
MatcherDumper.php in core/lib/Drupal/Core/Routing/MatcherDumper.php
MenuTreeStorage.php in core/lib/Drupal/Core/Menu/MenuTreeStorage.php
NoFieldsException.php in core/lib/Drupal/Core/Database/Query/NoFieldsException.php
NoUniqueFieldException.php in core/lib/Drupal/Core/Database/Query/NoUniqueFieldException.php
SchemaTableColumnSizeTooLargeException.php in core/lib/Drupal/Core/Database/Exception/SchemaTableColumnSizeTooLargeException.php
SchemaTableKeyTooLargeException.php in core/lib/Drupal/Core/Database/Exception/SchemaTableKeyTooLargeException.php
SchemaUniquePrefixedKeysIndexTestBase.php in core/tests/Drupal/KernelTests/Core/Database/SchemaUniquePrefixedKeysIndexTestBase.php
SessionHandler.php in core/lib/Drupal/Core/Session/SessionHandler.php
Sql.php in core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
SqlBase.php in core/modules/migrate/src/Plugin/migrate/source/SqlBase.php

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