diff --git a/packages/knex/src/error-handler.ts b/packages/knex/src/error-handler.ts
index 97ec4873a6..201d9528eb 100644
--- a/packages/knex/src/error-handler.ts
+++ b/packages/knex/src/error-handler.ts
@@ -65,7 +65,7 @@ export function errorHandler(error: any) {
     // NOTE: Error codes taken from
     // https://www.postgresql.org/docs/9.6/static/errcodes-appendix.html
     // Omit query information
-    const messages = error.message.split('-')
+    const messages = (error.message || '').split('-')
     error.message = messages[messages.length - 1]
 
     switch (error.code.slice(0, 2)) {
diff --git a/packages/knex/src/index.ts b/packages/knex/src/index.ts
index 59a59e1841..7f2c347302 100644
--- a/packages/knex/src/index.ts
+++ b/packages/knex/src/index.ts
@@ -37,6 +37,7 @@ export class KnexService<
 
   async create(data: Data, params?: ServiceParams): Promise<Result>
   async create(data: Data[], params?: ServiceParams): Promise<Result[]>
+  async create(data: Data | Data[], params?: ServiceParams): Promise<Result | Result[]>
   async create(data: Data | Data[], params?: ServiceParams): Promise<Result | Result[]> {
     if (Array.isArray(data) && !this.allowsMulti('create', params)) {
       throw new MethodNotAllowed('Can not create multiple entries')
@@ -54,6 +55,7 @@ export class KnexService<
 
   async patch(id: Id, data: PatchData, params?: ServiceParams): Promise<Result>
   async patch(id: null, data: PatchData, params?: ServiceParams): Promise<Result[]>
+  async patch(id: NullableId, data: PatchData, params?: ServiceParams): Promise<Result | Result[]>
   async patch(id: NullableId, data: PatchData, params?: ServiceParams): Promise<Result | Result[]> {
     const { $limit, ...query } = await this.sanitizeQuery(params)
 
@@ -65,6 +67,7 @@ export class KnexService<
 
   async remove(id: Id, params?: ServiceParams): Promise<Result>
   async remove(id: null, params?: ServiceParams): Promise<Result[]>
+  async remove(id: NullableId, params?: ServiceParams): Promise<Result | Result[]>
   async remove(id: NullableId, params?: ServiceParams): Promise<Result | Result[]> {
     const { $limit, ...query } = await this.sanitizeQuery(params)
 
diff --git a/packages/knex/test/error-handler.test.ts b/packages/knex/test/error-handler.test.ts
new file mode 100644
index 0000000000..04723a45d1
--- /dev/null
+++ b/packages/knex/test/error-handler.test.ts
@@ -0,0 +1,65 @@
+import assert from 'assert'
+import { errorHandler } from '../src'
+
+describe('Knex Error handler', () => {
+  it('sqlState', () => {
+    assert.throws(
+      () =>
+        errorHandler({
+          sqlState: '#23503'
+        }),
+      {
+        name: 'BadRequest'
+      }
+    )
+  })
+
+  it('sqliteError', () => {
+    assert.throws(
+      () =>
+        errorHandler({
+          code: 'SQLITE_ERROR',
+          errno: 1
+        }),
+      {
+        name: 'BadRequest'
+      }
+    )
+    assert.throws(() => errorHandler({ code: 'SQLITE_ERROR', errno: 2 }), { name: 'Unavailable' })
+    assert.throws(() => errorHandler({ code: 'SQLITE_ERROR', errno: 3 }), { name: 'Forbidden' })
+    assert.throws(() => errorHandler({ code: 'SQLITE_ERROR', errno: 12 }), { name: 'NotFound' })
+    assert.throws(() => errorHandler({ code: 'SQLITE_ERROR', errno: 13 }), { name: 'GeneralError' })
+  })
+
+  it('postgresqlError', () => {
+    assert.throws(
+      () =>
+        errorHandler({
+          code: '22P02',
+          message: 'Key (id)=(1) is not present in table "users".',
+          severity: 'ERROR',
+          routine: 'ExecConstraints'
+        }),
+      {
+        name: 'NotFound'
+      }
+    )
+    assert.throws(
+      () =>
+        errorHandler({ code: '2874', message: 'Something', severity: 'ERROR', routine: 'ExecConstraints' }),
+      {
+        name: 'Forbidden'
+      }
+    )
+    assert.throws(
+      () =>
+        errorHandler({ code: '3D74', message: 'Something', severity: 'ERROR', routine: 'ExecConstraints' }),
+      {
+        name: 'Unprocessable'
+      }
+    )
+    assert.throws(() => errorHandler({ code: 'XYZ', severity: 'ERROR', routine: 'ExecConstraints' }), {
+      name: 'GeneralError'
+    })
+  })
+})
diff --git a/packages/mongodb/src/adapter.ts b/packages/mongodb/src/adapter.ts
index b41c5125ba..d653de0969 100644
--- a/packages/mongodb/src/adapter.ts
+++ b/packages/mongodb/src/adapter.ts
@@ -281,9 +281,7 @@ export class MongoDbAdapter<
       ? model
           .insertMany(data.map(setId), writeOptions)
           .then(async (result) =>
-            Promise.all(
-              Object.values(result.insertedIds).map(async (_id) => model.findOne({ _id }, params.mongodb))
-            )
+            model.find({ _id: { $in: Object.values(result.insertedIds) } }, params.mongodb).toArray()
           )
       : model
           .insertOne(setId(data), writeOptions)
diff --git a/packages/mongodb/src/index.ts b/packages/mongodb/src/index.ts
index 1b86dffff1..e6b73579b5 100644
--- a/packages/mongodb/src/index.ts
+++ b/packages/mongodb/src/index.ts
@@ -32,6 +32,7 @@ export class MongoDBService<
 
   async create(data: Data, params?: ServiceParams): Promise<Result>
   async create(data: Data[], params?: ServiceParams): Promise<Result[]>
+  async create(data: Data | Data[], params?: ServiceParams): Promise<Result | Result[]>
   async create(data: Data | Data[], params?: ServiceParams): Promise<Result | Result[]> {
     if (Array.isArray(data) && !this.allowsMulti('create', params)) {
       throw new MethodNotAllowed('Can not create multiple entries')
@@ -49,6 +50,7 @@ export class MongoDBService<
 
   async patch(id: null, data: PatchData, params?: ServiceParams): Promise<Result[]>
   async patch(id: AdapterId, data: PatchData, params?: ServiceParams): Promise<Result>
+  async patch(id: NullableAdapterId, data: PatchData, params?: ServiceParams): Promise<Result | Result[]>
   async patch(id: NullableAdapterId, data: PatchData, params?: ServiceParams): Promise<Result | Result[]> {
     const { $limit, ...query } = await this.sanitizeQuery(params)
 
@@ -60,6 +62,7 @@ export class MongoDBService<
 
   async remove(id: AdapterId, params?: ServiceParams): Promise<Result>
   async remove(id: null, params?: ServiceParams): Promise<Result[]>
+  async remove(id: NullableAdapterId, params?: ServiceParams): Promise<Result | Result[]>
   async remove(id: NullableAdapterId, params?: ServiceParams): Promise<Result | Result[]> {
     const { $limit, ...query } = await this.sanitizeQuery(params)