diff --git a/types/data-api-client/data-api-client-tests.ts b/types/data-api-client/data-api-client-tests.ts
index b078259a767004..a1fd83e142fa74 100644
--- a/types/data-api-client/data-api-client-tests.ts
+++ b/types/data-api-client/data-api-client-tests.ts
@@ -1,6 +1,6 @@
 import Client = require('data-api-client');
 
-const client = Client({
+const client: Client.iDataAPIClient = Client({
     resourceArn: '',
     secretArn: '',
     database: '',
@@ -24,15 +24,13 @@ client.query({ sql: 'SELECT * FROM Users;', parameters: {}, transactionId: '' })
     }
 });
 
-client
-    .query<{ id: string; name: string }>('SELECT * FROM Users WHERE id = :id;', { id: 'id' })
-    .then(res => {
-        if (res.records?.length) {
-            const user = res.records[0];
-            user.id;
-            user.name;
-        }
-    });
+client.query<{ id: string; name: string }>('SELECT * FROM Users WHERE id = :id;', { id: 'id' }).then(res => {
+    if (res.records?.length) {
+        const user = res.records[0];
+        user.id;
+        user.name;
+    }
+});
 
 client
     .transaction()
diff --git a/types/data-api-client/index.d.ts b/types/data-api-client/index.d.ts
index b37b443d128297..c0626e041013fa 100644
--- a/types/data-api-client/index.d.ts
+++ b/types/data-api-client/index.d.ts
@@ -9,66 +9,67 @@
 /// <reference types="node" />
 
 import type { ClientConfiguration, Types } from 'aws-sdk/clients/rdsdataservice';
+declare namespace Client {
+    type OmittedValues = 'database' | 'resourceArn' | 'secretArn' | 'schema';
 
-type OmittedValues = 'database' | 'resourceArn' | 'secretArn' | 'schema';
-
-interface iParams {
-    secretArn: string;
-    resourceArn: string;
-    database?: string | undefined;
-    keepAlive?: boolean | undefined;
-    hydrateColumnNames?: boolean | undefined;
-    sslEnabled?: boolean | undefined;
-    options?: ClientConfiguration | undefined;
-    region?: string | undefined;
-    engine?: 'mysql' | 'pg' | undefined;
-    formatOptions?: {
-        deserializeDate?: boolean | undefined;
-        treatAsLocalDate?: boolean | undefined;
-    } | undefined;
-}
-
-interface Transaction {
-    query(sql: string, params?: [] | unknown): Transaction; // params can be [] or {};
-    query(
-        obj:
+    interface iParams {
+        secretArn: string;
+        resourceArn: string;
+        database?: string | undefined;
+        keepAlive?: boolean | undefined;
+        hydrateColumnNames?: boolean | undefined;
+        sslEnabled?: boolean | undefined;
+        options?: ClientConfiguration | undefined;
+        region?: string | undefined;
+        engine?: 'mysql' | 'pg' | undefined;
+        formatOptions?:
             | {
-                  sql: string;
-                  parameters: [] | unknown;
-                  database?: string | undefined;
-                  hydrateColumnNames?: boolean | undefined;
+                  deserializeDate?: boolean | undefined;
+                  treatAsLocalDate?: boolean | undefined;
               }
-            | ((prevResult: { insertId?: any }) => any),
-    ): Transaction;
-
-    rollback: (error: Error, status: any) => void;
-    commit: () => Promise<void>;
-}
+            | undefined;
+    }
 
-interface iDataAPIClient {
-    /* tslint:disable:no-unnecessary-generics */
-    query<T = any>(sql: string, params?: [] | unknown): Promise<iDataAPIQueryResult<T>>; // params can be [] or {};
-    query<T = any>(obj: {
-        sql: string;
-        parameters?: [] | unknown | undefined;
-        transactionId?: string | undefined;
-        database?: string | undefined;
-        hydrateColumnNames?: boolean | undefined;
-    }): Promise<iDataAPIQueryResult<T>>;
-    transaction(): Transaction; // needs to return an interface with
+    interface Transaction {
+        query(sql: string, params?: [] | unknown): Transaction; // params can be [] or {};
+        query(
+            obj:
+                | {
+                      sql: string;
+                      parameters: [] | unknown;
+                      database?: string | undefined;
+                      hydrateColumnNames?: boolean | undefined;
+                  }
+                | ((prevResult: { insertId?: any }) => any),
+        ): Transaction;
 
-    // promisified versions of the RDSDataService methods
-    batchExecuteStatement: (params: Omit<Types.BatchExecuteStatementRequest, OmittedValues>) => Promise<any>;
-    beginTransaction: () => Promise<Types.BeginTransactionResponse>;
-    commitTransaction: (params: Omit<Types.CommitTransactionRequest, OmittedValues>) => Promise<any>;
-    executeStatement: (params: Omit<Types.ExecuteStatementRequest, OmittedValues>) => Promise<any>;
-    rollbackTransaction: (params: Omit<Types.RollbackTransactionRequest, OmittedValues>) => Promise<any>;
-}
+        rollback: (error: Error, status: any) => void;
+        commit: () => Promise<void>;
+    }
 
-interface iDataAPIQueryResult<T = any> {
-    records: T[];
-}
+    interface iDataAPIClient {
+        /* tslint:disable:no-unnecessary-generics */
+        query<T = any>(sql: string, params?: [] | unknown): Promise<iDataAPIQueryResult<T>>; // params can be [] or {};
+        query<T = any>(obj: {
+            sql: string;
+            parameters?: [] | unknown | undefined;
+            transactionId?: string | undefined;
+            database?: string | undefined;
+            hydrateColumnNames?: boolean | undefined;
+        }): Promise<iDataAPIQueryResult<T>>;
+        transaction(): Transaction; // needs to return an interface with
 
-declare function Client(params: iParams): iDataAPIClient;
+        // promisified versions of the RDSDataService methods
+        batchExecuteStatement: (params: Omit<Types.BatchExecuteStatementRequest, OmittedValues>) => Promise<any>;
+        beginTransaction: () => Promise<Types.BeginTransactionResponse>;
+        commitTransaction: (params: Omit<Types.CommitTransactionRequest, OmittedValues>) => Promise<any>;
+        executeStatement: (params: Omit<Types.ExecuteStatementRequest, OmittedValues>) => Promise<any>;
+        rollbackTransaction: (params: Omit<Types.RollbackTransactionRequest, OmittedValues>) => Promise<any>;
+    }
 
+    interface iDataAPIQueryResult<T = any> {
+        records: T[];
+    }
+}
+declare function Client(params: Client.iParams): Client.iDataAPIClient;
 export = Client;