diff --git a/backend/src/index.ts b/backend/src/index.ts
index 6cc4ca4..e914451 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -249,7 +249,7 @@ app.listen(PORT, async () => {
     if (db) {
       await db.ensureInitialized?.();
       try {
-        const schemaRow = await (db as any).queryOne<{ count: number }>(
+        const schemaRow = await (db.queryOne as <T>(sql: string, params?: any[]) => Promise<T | null>)<{ count: number }>(
           `SELECT COUNT(*) as count FROM schemas`
         );
         hasSchemas = (schemaRow?.count || 0) > 0;
diff --git a/backend/src/services/dataIntegrityService.ts b/backend/src/services/dataIntegrityService.ts
index 284f828..9fff3da 100644
--- a/backend/src/services/dataIntegrityService.ts
+++ b/backend/src/services/dataIntegrityService.ts
@@ -8,6 +8,7 @@ import { logger } from './logger.js';
 import { normalizedCacheStore as cacheStore } from './normalizedCacheStore.js';
 import { jiraAssetsClient, JiraObjectNotFoundError } from './jiraAssetsClient.js';
 import type { CMDBObject } from '../generated/jira-types.js';
+import type { DatabaseAdapter } from './database/interface.js';
 
 export interface BrokenReference {
   object_id: string;
@@ -150,7 +151,8 @@ class DataIntegrityService {
     // 1. Check cache first
     const db = (cacheStore as any).db;
     if (db) {
-      const objRow = await db.queryOne<{
+      const typedDb = db as DatabaseAdapter;
+      const objRow = await typedDb.queryOne<{
         id: string;
         object_type_name: string;
       }>(`
diff --git a/backend/src/services/dataService.ts b/backend/src/services/dataService.ts
index 06dab4d..b4428f8 100644
--- a/backend/src/services/dataService.ts
+++ b/backend/src/services/dataService.ts
@@ -12,6 +12,7 @@ import { normalizedCacheStore } from './normalizedCacheStore.js';
 import { jiraAssetsClient } from './jiraAssetsClient.js';
 import { jiraAssetsService } from './jiraAssets.js';
 import { logger } from './logger.js';
+import type { DatabaseAdapter } from './database/interface.js';
 import type { 
   ApplicationComponent, 
   IctGovernanceModel, 
@@ -126,7 +127,8 @@ async function getDescriptionFromDatabase(objectId: string): Promise<string | nu
     const descriptionFieldNames = ['description', 'Description', 'DESCRIPTION'];
     
     // First, get the object to find its type
-    const objRow = await db.queryOne<{ object_type_name: string }>(`
+    const typedDb = db as DatabaseAdapter;
+    const objRow = await typedDb.queryOne<{ object_type_name: string }>(`
       SELECT object_type_name FROM objects WHERE id = ?
     `, [objectId]);
     
@@ -134,7 +136,7 @@ async function getDescriptionFromDatabase(objectId: string): Promise<string | nu
     
     // Try each possible description field name
     for (const fieldName of descriptionFieldNames) {
-      const descRow = await db.queryOne<{ text_value: string }>(`
+      const descRow = await typedDb.queryOne<{ text_value: string }>(`
         SELECT av.text_value
         FROM attribute_values av
         JOIN attributes a ON av.attribute_id = a.id
@@ -173,7 +175,8 @@ async function toReferenceValue(ref: ObjectReference | null | undefined): Promis
       await db.ensureInitialized?.();
       
       // Get basic object info from database
-      const objRow = await db.queryOne<{
+      const typedDb = db as DatabaseAdapter;
+      const objRow = await typedDb.queryOne<{
         id: string;
         object_key: string;
         label: string;
diff --git a/backend/src/services/database/fix-object-types-constraints.ts b/backend/src/services/database/fix-object-types-constraints.ts
index 49b011a..f821ace 100644
--- a/backend/src/services/database/fix-object-types-constraints.ts
+++ b/backend/src/services/database/fix-object-types-constraints.ts
@@ -7,14 +7,15 @@
 
 import { logger } from '../logger.js';
 import { normalizedCacheStore } from '../normalizedCacheStore.js';
+import type { DatabaseAdapter } from './interface.js';
 
 export async function fixObjectTypesConstraints(): Promise<void> {
-  const db = (normalizedCacheStore as any).db;
+  const db = (normalizedCacheStore as any).db as DatabaseAdapter;
   if (!db) {
     throw new Error('Database not available');
   }
 
-  await db.ensureInitialized?.();
+  await (db as any).ensureInitialized?.();
 
   logger.info('Migration: Fixing UNIQUE constraints on object_types table...');
 
diff --git a/backend/src/services/jiraAssets.ts b/backend/src/services/jiraAssets.ts
index a4d652a..a1e6185 100644
--- a/backend/src/services/jiraAssets.ts
+++ b/backend/src/services/jiraAssets.ts
@@ -16,6 +16,7 @@ import type {
   TeamDashboardData,
 } from '../types/index.js';
 import type { CMDBObjectTypeName } from '../generated/jira-types.js';
+import type { DatabaseAdapter } from './database/interface.js';
 
 // Attribute name mappings (these should match your Jira Assets schema)
 const ATTRIBUTE_NAMES = {
@@ -126,7 +127,8 @@ class JiraAssetsService {
       if (!db) return null;
       
       await db.ensureInitialized?.();
-      const schemaRow = await db.queryOne<{ jira_schema_id: string }>(
+      const typedDb = db as DatabaseAdapter;
+      const schemaRow = await typedDb.queryOne<{ jira_schema_id: string }>(
         `SELECT jira_schema_id FROM schemas ORDER BY jira_schema_id LIMIT 1`
       );
       return schemaRow?.jira_schema_id || null;
@@ -146,9 +148,10 @@ class JiraAssetsService {
       if (!db) return [];
       
       await db.ensureInitialized?.();
-      const schemaRows = await db.query<{ jira_schema_id: string }>(
+      const typedDb = db as DatabaseAdapter;
+      const schemaRows = await typedDb.query<{ jira_schema_id: string }>(
         `SELECT DISTINCT jira_schema_id FROM schemas WHERE search_enabled = ? ORDER BY jira_schema_id`,
-        [db.isPostgres ? true : 1]
+        [typedDb.isPostgres ? true : 1]
       );
       return schemaRows.map((row: { jira_schema_id: string }) => row.jira_schema_id);
     } catch (error) {
diff --git a/backend/src/services/schemaMappingService.ts b/backend/src/services/schemaMappingService.ts
index 2555048..f3e9fe7 100644
--- a/backend/src/services/schemaMappingService.ts
+++ b/backend/src/services/schemaMappingService.ts
@@ -9,6 +9,7 @@ import { logger } from './logger.js';
 import { normalizedCacheStore } from './normalizedCacheStore.js';
 import { config } from '../config/env.js';
 import type { CMDBObjectTypeName } from '../generated/jira-types.js';
+import type { DatabaseAdapter } from './database/interface.js';
 
 export interface SchemaMapping {
   objectTypeName: string;
@@ -61,7 +62,8 @@ class SchemaMappingService {
 
     await db.ensureInitialized?.();
 
-    const rows = await db.query<{
+    const typedDb = db as DatabaseAdapter;
+    const rows = await typedDb.query<{
       object_type_name: string;
       schema_id: string;
       enabled: boolean | number;
@@ -158,7 +160,8 @@ class SchemaMappingService {
       const db = (normalizedCacheStore as any).db;
       if (db) {
         await db.ensureInitialized?.();
-        const row = await db.queryOne<{ enabled: boolean | number }>(`
+        const typedDb = db as DatabaseAdapter;
+        const row = await typedDb.queryOne<{ enabled: boolean | number }>(`
           SELECT enabled FROM schema_mappings WHERE object_type_name = ?
         `, [objectTypeName]);
         
@@ -195,7 +198,8 @@ class SchemaMappingService {
       await db.ensureInitialized?.();
 
       // Use parameterized query to avoid boolean/integer comparison issues
-      const rows = await db.query<{
+      const typedDb = db as DatabaseAdapter;
+      const rows = await typedDb.query<{
         object_type_name: string;
         schema_id: string;
         enabled: boolean | number;
@@ -243,7 +247,8 @@ class SchemaMappingService {
 
     try {
       // Get all object types with their mappings
-      const rows = await db.query<{
+      const typedDb = db as DatabaseAdapter;
+      const rows = await typedDb.query<{
         type_name: string;
         display_name: string;
         description: string | null;
@@ -274,7 +279,8 @@ class SchemaMappingService {
         const db = (normalizedCacheStore as any).db;
         if (db) {
           await db.ensureInitialized?.();
-          const schemaRow = await db.queryOne<{ jira_schema_id: string }>(
+          const typedDb = db as DatabaseAdapter;
+          const schemaRow = await typedDb.queryOne<{ jira_schema_id: string }>(
             `SELECT jira_schema_id FROM schemas ORDER BY jira_schema_id LIMIT 1`
           );
           defaultSchemaId = schemaRow?.jira_schema_id || null;
@@ -283,7 +289,7 @@ class SchemaMappingService {
         logger.warn('SchemaMapping: Failed to get default schema ID from database', error);
       }
 
-      return rows.map((row: { type_name: string; display_name: string; description: string | null; schema_id: string; enabled: boolean | number; created_at: string; updated_at: string }) => ({
+      return rows.map((row: { type_name: string; display_name: string; description: string | null; object_count: number; sync_priority: number; schema_id: string | null; enabled: number | boolean | null }) => ({
         typeName: row.type_name,
         displayName: row.display_name,
         description: row.description,
@@ -291,8 +297,8 @@ class SchemaMappingService {
         enabled: row.enabled === null 
           ? true // Default: enabled if no mapping exists
           : (typeof row.enabled === 'boolean' ? row.enabled : row.enabled === 1),
-        objectCount: (row as any).object_count || 0,
-        syncPriority: (row as any).sync_priority || 0,
+        objectCount: row.object_count || 0,
+        syncPriority: row.sync_priority || 0,
       }));
     } catch (error) {
       logger.error('SchemaMappingService: Failed to get object types with config', error);
@@ -312,7 +318,8 @@ class SchemaMappingService {
     await db.ensureInitialized?.();
 
     // Check if mapping exists
-    const existing = await db.queryOne<{ schema_id: string }>(`
+    const typedDb = db as DatabaseAdapter;
+    const existing = await typedDb.queryOne<{ schema_id: string }>(`
       SELECT schema_id FROM schema_mappings WHERE object_type_name = ?
     `, [objectTypeName]);