fix(server): close duckdb resources on load failure, dedupe concurrent loads, drop unused cells projection

apps/server/src/core/base/query-cache/base-query-cache.service.ts

@@ -40,6 +40,7 @@ export class BaseQueryCacheService
 {
   private readonly logger = new Logger(BaseQueryCacheService.name);
   private readonly collections = new Map<string, LoadedCollection>();
+  private readonly inFlightLoads = new Map<string, Promise<LoadedCollection>>();
 
   constructor(
     private readonly configProvider: QueryCacheConfigProvider,
@@ -168,6 +169,8 @@ export class BaseQueryCacheService
     baseId: string,
     workspaceId: string,
   ): Promise<LoadedCollection> {
+    // TODO(task-7): remove per-request findById once pub/sub invalidation
+    // keeps collections in sync with schema bumps.
     const existing = this.collections.get(baseId);
 
     const base = await this.baseRepo.findById(baseId);
@@ -186,14 +189,24 @@ export class BaseQueryCacheService
       this.collections.delete(baseId);
     }
 
+    const inFlight = this.inFlightLoads.get(baseId);
+    if (inFlight) return inFlight;
+
+    const promise = (async () => {
+      try {
         const { maxCollections } = this.configProvider.config;
         if (this.collections.size >= maxCollections) {
           this.evictLru();
         }
-
         const loaded = await this.collectionLoader.load(baseId, workspaceId);
         this.collections.set(baseId, loaded);
         return loaded;
+      } finally {
+        this.inFlightLoads.delete(baseId);
+      }
+    })();
+    this.inFlightLoads.set(baseId, promise);
+    return promise;
   }
 
   private evictLru(): void {
@@ -228,10 +241,10 @@ export class BaseQueryCacheService
 }
 
 // Convert a DuckDB row object back into the BaseRow JSON shape. The builder
-// projects `cells` as a json_object keyed by property id; typed columns
-// (DOUBLE, BOOLEAN, TIMESTAMPTZ) round-trip as JS primitives / Date objects.
-// We reconstruct `cells` directly from the per-property columns so the JSON
-// payload matches what Postgres returns.
+// projects one column per user property; typed columns (DOUBLE, BOOLEAN,
+// TIMESTAMPTZ) round-trip as JS primitives / Date objects. We reconstruct
+// `cells` directly from the per-property columns so the JSON payload matches
+// what Postgres returns.
 function shapeBaseRow(
   raw: Record<string, unknown>,
   specs: ColumnSpec[],

apps/server/src/core/base/query-cache/collection-loader.ts

@@ -38,13 +38,16 @@ export class CollectionLoader {
 
     const instance = await DuckDBInstance.create(':memory:');
     const connection = await instance.connect();
+    let appender: Awaited<ReturnType<typeof connection.createAppender>> | null =
+      null;
 
+    try {
       const ddl = `CREATE TABLE rows (${specs
         .map((s) => `${quoteIdent(s.column)} ${s.ddlType}`)
         .join(', ')}, PRIMARY KEY (${quoteIdent('id')}))`;
       await connection.run(ddl);
 
-    const appender = await connection.createAppender('rows');
+      appender = await connection.createAppender('rows');
 
       let rowCount = 0;
       for await (const chunk of this.baseRowRepo.streamByBaseId(baseId, {
@@ -100,6 +103,7 @@ export class CollectionLoader {
       }
       appender.flushSync();
       appender.closeSync();
+      appender = null;
 
       for (const spec of specs) {
         if (!spec.indexable) continue;
@@ -121,6 +125,26 @@ export class CollectionLoader {
         connection,
         lastAccessedAt: Date.now(),
       };
+    } catch (err) {
+      if (appender) {
+        try {
+          appender.closeSync();
+        } catch {
+          // swallow — best-effort cleanup
+        }
+      }
+      try {
+        connection.closeSync();
+      } catch {
+        // swallow — best-effort cleanup
+      }
+      try {
+        instance.closeSync();
+      } catch {
+        // swallow — best-effort cleanup
+      }
+      throw err;
+    }
   }
 }
 

apps/server/src/core/base/query-cache/duckdb-query-builder.ts

@@ -97,11 +97,9 @@ export function buildDuckDbListQuery(
 // --- select projection -------------------------------------------------
 
 function buildSelect(index: ColumnIndex, sortBuilds: SortBuild[]): string[] {
-  const cellsJson = buildCellsJson(index.userColumns);
   const parts: string[] = [
     'id',
     'base_id',
-    `${cellsJson} AS cells`,
     'position',
     'creator_id',
     'last_updated_by_id',
@@ -110,22 +108,15 @@ function buildSelect(index: ColumnIndex, sortBuilds: SortBuild[]): string[] {
     'updated_at',
     'deleted_at',
   ];
+  for (const col of index.userColumns) {
+    parts.push(quoteIdent(col.column));
+  }
   for (const sb of sortBuilds) {
     parts.push(`${sb.expression} AS ${sb.key}`);
   }
   return parts;
 }
 
-function buildCellsJson(userColumns: ColumnSpec[]): string {
-  if (userColumns.length === 0) return `'{}'::JSON`;
-  const entries: string[] = [];
-  for (const col of userColumns) {
-    entries.push(`'${col.column}'`);
-    entries.push(quoteIdent(col.column));
-  }
-  return `json_object(${entries.join(', ')})`;
-}
-
 // --- filter ------------------------------------------------------------
 
 function buildFilter(