11 files declare their use of StatementInterface

Connection.php in core/modules/sqlite/src/Driver/Database/sqlite/Connection.php
Connection.php in core/modules/pgsql/src/Driver/Database/pgsql/Connection.php
ExceptionHandler.php in core/modules/mysql/src/Driver/Database/mysql/ExceptionHandler.php
FetchTest.php in core/tests/Drupal/KernelTests/Core/Database/FetchTest.php
HelpSearch.php in core/modules/help/src/Plugin/Search/HelpSearch.php
node.module in core/modules/node/node.module
The core module that allows content to be submitted to the site.
NodeSearch.php in core/modules/node/src/Plugin/Search/NodeSearch.php
PagerPluginBaseTest.php in core/modules/views/tests/src/Unit/Plugin/pager/PagerPluginBaseTest.php
SqlBaseTest.php in core/modules/migrate/tests/src/Kernel/SqlBaseTest.php
Statement.php in core/modules/sqlite/src/Driver/Database/sqlite/Statement.php
StatementTest.php in core/tests/Drupal/KernelTests/Core/Database/StatementTest.php

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