120 files declare their use of Connection

AliasRepository.php in core/lib/Drupal/Core/Path/AliasRepository.php
AliasStorage.php in core/lib/Drupal/Core/Path/AliasStorage.php
AssignOwnerNode.php in core/modules/node/src/Plugin/Action/AssignOwnerNode.php
BanIpManager.php in core/modules/ban/src/BanIpManager.php
BatchStorage.php in core/lib/Drupal/Core/Batch/BatchStorage.php
BookOutlineStorage.php in core/modules/book/src/BookOutlineStorage.php
CommentStatistics.php in core/modules/comment/src/CommentStatistics.php
CommentStorage.php in core/modules/comment/src/CommentStorage.php
Condition.php in core/lib/Drupal/Core/Database/Query/Condition.php
ConditionInterface.php in core/lib/Drupal/Core/Database/Query/ConditionInterface.php
ConditionTest.php in core/tests/Drupal/Tests/Core/Database/ConditionTest.php
Connection.php in core/tests/fixtures/database_drivers/custom/fake/Connection.php
Connection.php in core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php
Connection.php in core/lib/Drupal/Core/Database/Driver/mysql/Connection.php
Connection.php in core/lib/Drupal/Core/Database/Driver/pgsql/Connection.php
Cookie.php in core/modules/user/src/Authentication/Provider/Cookie.php
CredentialForm.php in core/modules/migrate_drupal_ui/src/Form/CredentialForm.php
DatabaseBackend.php in core/lib/Drupal/Core/Flood/DatabaseBackend.php
DatabaseBackend.php in core/lib/Drupal/Core/Cache/DatabaseBackend.php
DatabaseBackendFactory.php in core/lib/Drupal/Core/Cache/DatabaseBackendFactory.php
DatabaseBackendFactoryTest.php in core/tests/Drupal/Tests/Core/Cache/DatabaseBackendFactoryTest.php
DatabaseCacheTagsChecksum.php in core/lib/Drupal/Core/Cache/DatabaseCacheTagsChecksum.php
DatabaseFileUsageBackend.php in core/modules/file/src/FileUsage/DatabaseFileUsageBackend.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/Config/DatabaseStorage.php
DatabaseStorage.php in core/lib/Drupal/Core/KeyValueStore/DatabaseStorage.php
DatabaseStorageExpirable.php in core/lib/Drupal/Core/KeyValueStore/DatabaseStorageExpirable.php
DatabaseTestController.php in core/modules/system/tests/modules/database_test/src/Controller/DatabaseTestController.php
DbDumpCommand.php in core/lib/Drupal/Core/Command/DbDumpCommand.php
DbImportCommand.php in core/lib/Drupal/Core/Command/DbImportCommand.php
DbLog.php in core/modules/dblog/src/Logger/DbLog.php
DblogClearLogConfirmForm.php in core/modules/dblog/src/Form/DblogClearLogConfirmForm.php
DbLogController.php in core/modules/dblog/src/Controller/DbLogController.php
Delete.php in core/lib/Drupal/Core/Database/Query/Delete.php
Drupal6SqlBaseTest.php in core/modules/migrate_drupal/tests/src/Unit/source/d6/Drupal6SqlBaseTest.php
Contains \Drupal\Tests\migrate_drupal\Unit\source\d6\Drupal6SqlBaseTest.
DrupalSqlBaseTest.php in core/modules/migrate_drupal/tests/src/Unit/source/DrupalSqlBaseTest.php
EntityReference.php in core/modules/views/src/Plugin/views/display/EntityReference.php
EnvironmentCleaner.php in core/lib/Drupal/Core/Test/EnvironmentCleaner.php
EnvironmentCleanerService.php in core/modules/simpletest/src/EnvironmentCleanerService.php
EnvironmentCleanerTest.php in core/tests/Drupal/KernelTests/Core/Test/EnvironmentCleanerTest.php
ErrorTestController.php in core/modules/system/tests/modules/error_test/src/Controller/ErrorTestController.php
ExceptionDetectNeedsInstallSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ExceptionDetectNeedsInstallSubscriber.php
ExportStorageManager.php in core/lib/Drupal/Core/Config/ExportStorageManager.php
ForumIndexStorage.php in core/modules/forum/src/ForumIndexStorage.php
ForumManager.php in core/modules/forum/src/ForumManager.php
HelpSearch.php in core/modules/help_topics/src/Plugin/Search/HelpSearch.php
ImportStorageTransformer.php in core/lib/Drupal/Core/Config/ImportStorageTransformer.php
InlineBlockEntityOperations.php in core/modules/layout_builder/src/InlineBlockEntityOperations.php
InlineBlockUsage.php in core/modules/layout_builder/src/InlineBlockUsage.php
InlineBlockUsageTest.php in core/modules/layout_builder/tests/src/Unit/InlineBlockUsageTest.php
InstallerRedirectTrait.php in core/lib/Drupal/Core/Installer/InstallerRedirectTrait.php
InstallerRedirectTraitTest.php in core/tests/Drupal/KernelTests/Core/Installer/InstallerRedirectTraitTest.php
KeyValueDatabaseExpirableFactory.php in core/lib/Drupal/Core/KeyValueStore/KeyValueDatabaseExpirableFactory.php
KeyValueDatabaseFactory.php in core/lib/Drupal/Core/KeyValueStore/KeyValueDatabaseFactory.php
LegacyFileTest.php in core/modules/file/tests/src/Unit/LegacyFileTest.php
LonelyMonkeyClass.php in core/modules/system/tests/modules/error_service_test/src/LonelyMonkeyClass.php
MatcherDumper.php in core/lib/Drupal/Core/Routing/MatcherDumper.php
MenuDeleteForm.php in core/modules/menu_ui/src/Form/MenuDeleteForm.php
MenuRouterRebuildSubscriber.php in core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php
MenuTreeStorage.php in core/lib/Drupal/Core/Menu/MenuTreeStorage.php
Merge.php in core/lib/Drupal/Core/Database/Query/Merge.php
MigrationConfigurationTrait.php in core/modules/migrate_drupal/src/MigrationConfigurationTrait.php
MysqlDateSql.php in core/modules/views/src/Plugin/views/query/MysqlDateSql.php
MysqlDateSqlTest.php in core/modules/views/tests/src/Unit/Plugin/views/query/MysqlDateSqlTest.php
NodeCounter.php in core/modules/statistics/src/Plugin/migrate/destination/NodeCounter.php
NodeGrantDatabaseStorage.php in core/modules/node/src/NodeGrantDatabaseStorage.php
NodeMigrateType.php in core/modules/migrate_drupal/src/NodeMigrateType.php
NodeNewComments.php in core/modules/comment/src/Plugin/views/field/NodeNewComments.php
NodeRevisionDeleteForm.php in core/modules/node/src/Form/NodeRevisionDeleteForm.php
NodeSearch.php in core/modules/node/src/Plugin/Search/NodeSearch.php
NodeStatisticsDatabaseStorage.php in core/modules/statistics/src/NodeStatisticsDatabaseStorage.php
PagerSelectExtender.php in core/lib/Drupal/Core/Database/Query/PagerSelectExtender.php
PersistentDatabaseLockBackend.php in core/lib/Drupal/Core/Lock/PersistentDatabaseLockBackend.php
PgsqlQueryFactory.php in core/modules/workspaces/src/EntityQuery/PgsqlQueryFactory.php
PostgresqlDateSql.php in core/modules/views/src/Plugin/views/query/PostgresqlDateSql.php
PostgresqlDateSqlTest.php in core/modules/views/tests/src/Unit/Plugin/views/query/PostgresqlDateSqlTest.php
Query.php in core/lib/Drupal/Core/Database/Query/Query.php
Query.php in core/lib/Drupal/Core/Entity/Query/Sql/Query.php
QueryConditionTrait.php in core/lib/Drupal/Core/Database/Query/QueryConditionTrait.php
QueryFactory.php in core/modules/workspaces/src/EntityQuery/QueryFactory.php
QueryFactory.php in core/lib/Drupal/Core/Entity/Query/Sql/QueryFactory.php
QueryTrait.php in core/modules/workspaces/src/EntityQuery/QueryTrait.php
QueueDatabaseFactory.php in core/lib/Drupal/Core/Queue/QueueDatabaseFactory.php
Roles.php in core/modules/user/src/Plugin/views/field/Roles.php
RouteProvider.php in core/lib/Drupal/Core/Routing/RouteProvider.php
RoutingFixtures.php in core/tests/Drupal/Tests/Core/Routing/RoutingFixtures.php
SearchIndex.php in core/modules/search/src/SearchIndex.php
Select.php in core/lib/Drupal/Core/Database/Query/Select.php
SelectExtender.php in core/lib/Drupal/Core/Database/Query/SelectExtender.php
SelectInterface.php in core/lib/Drupal/Core/Database/Query/SelectInterface.php
SessionHandler.php in core/lib/Drupal/Core/Session/SessionHandler.php
SessionManager.php in core/lib/Drupal/Core/Session/SessionManager.php
SetInlineBlockDependency.php in core/modules/layout_builder/src/EventSubscriber/SetInlineBlockDependency.php
ShortcutSetDeleteForm.php in core/modules/shortcut/src/Form/ShortcutSetDeleteForm.php
ShortcutSetStorage.php in core/modules/shortcut/src/ShortcutSetStorage.php
SimpletestResultsForm.php in core/modules/simpletest/src/Form/SimpletestResultsForm.php
SqlContentEntityStorage.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
SqlContentEntityStorageSchema.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
SqliteDateSql.php in core/modules/views/src/Plugin/views/query/SqliteDateSql.php
SqliteDateSqlTest.php in core/modules/views/tests/src/Unit/Plugin/views/query/SqliteDateSqlTest.php
StringDatabaseStorage.php in core/modules/locale/src/StringDatabaseStorage.php
StringFilter.php in core/modules/views/src/Plugin/views/filter/StringFilter.php
StubConnection.php in core/tests/Drupal/Tests/Core/Database/Stub/StubConnection.php
TableSortExtender.php in core/lib/Drupal/Core/Database/Query/TableSortExtender.php
TestDeprecatedTestHooks.php in core/modules/simpletest/tests/src/Kernel/TestDeprecatedTestHooks.php
TestSqlIdMap.php in core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
TrackerController.php in core/modules/tracker/src/Controller/TrackerController.php
Truncate.php in core/lib/Drupal/Core/Database/Query/Truncate.php
Update.php in core/lib/Drupal/Core/Database/Query/Update.php
Upsert.php in core/lib/Drupal/Core/Database/Query/Upsert.php
UserData.php in core/modules/user/src/UserData.php
UserSearch.php in core/modules/user/src/Plugin/Search/UserSearch.php
UserSelection.php in core/modules/user/src/Plugin/EntityReferenceSelection/UserSelection.php
UserUid.php in core/modules/comment/src/Plugin/views/argument/UserUid.php
Vid.php in core/modules/node/src/Plugin/views/argument/Vid.php
WorkspaceAssociation.php in core/modules/workspaces/src/WorkspaceAssociation.php
WorkspaceMerger.php in core/modules/workspaces/src/WorkspaceMerger.php
WorkspaceOperationFactory.php in core/modules/workspaces/src/WorkspaceOperationFactory.php
WorkspacePublisher.php in core/modules/workspaces/src/WorkspacePublisher.php

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