Add runtime statistics via engine.stats

src/sqlmem/executor.py

@@ -5,13 +5,21 @@ from loguru import logger
 from .cache import CacheManager
 from .parser import ParsedQuery
 from .registry import ColumnRegistry
+from .stats import StatsCollector
 
 
 class QueryExecutor:
-    def __init__(self, cache: CacheManager, registry: ColumnRegistry, source_conn: sqlite3.Connection) -> None:
+    def __init__(
+        self,
+        cache: CacheManager,
+        registry: ColumnRegistry,
+        source_conn: sqlite3.Connection,
+        stats: StatsCollector,
+    ) -> None:
         self._cache = cache
         self._registry = registry
         self._source_conn = source_conn
+        self._stats = stats
 
     def execute(self, parsed: ParsedQuery) -> list[dict]:
         table = parsed.table
@@ -26,11 +34,15 @@ class QueryExecutor:
                     f"Re-fetching {table!r} — new columns requested: {missing}. "
                     f"Expanding cache from {self._registry.get_columns(table)} + {missing}"
                 )
+                self._stats.record_refetch()
+            else:
+                self._stats.record_miss()
             all_columns = list(self._registry.get_columns(table)) + missing
             self._cache.load_table(table, all_columns, self._source_conn)
             self._registry.update(table, all_columns)
         else:
             logger.debug(f"Cache hit: {table!r} columns={columns}")
+            self._stats.record_hit()
 
         return self._run_in_memory(parsed)