MSSQL storage

The MSSQL storage implementation provides a production-ready storage solution using Microsoft SQL Server databases.

Installation

npm install @mastra/mssql@latest

Usage

import { MSSQLStore } from '@mastra/mssql'

const storage = new MSSQLStore({
  id: 'mssql-storage',
  connectionString: process.env.DATABASE_URL,
})

Parameters

<PropertiesTable content={[ { name: 'connectionString', type: 'string', description: 'MSSQL connection string (e.g., Server=localhost,1433;Database=mydb;User Id=sa;Password=password;Encrypt=true;TrustServerCertificate=true)', isOptional: false, }, { name: 'schemaName', type: 'string', description: 'The name of the schema you want the storage to use. Will use the default schema if not provided.', isOptional: true, }, ]} />

Constructor examples

You can instantiate MSSQLStore in the following ways:

import { MSSQLStore } from '@mastra/mssql'

// Using a connection string only
const store1 = new MSSQLStore({
  id: 'mssql-storage-1',
  connectionString:
    'Server=localhost,1433;Database=mydb;User Id=sa;Password=password;Encrypt=true;TrustServerCertificate=true',
})

// Using a connection string with a custom schema name
const store2 = new MSSQLStore({
  id: 'mssql-storage-2',
  connectionString:
    'Server=localhost,1433;Database=mydb;User Id=sa;Password=password;Encrypt=true;TrustServerCertificate=true',
  schemaName: 'custom_schema', // optional
})

// Using individual connection parameters
const store4 = new MSSQLStore({
  id: 'mssql-storage-3',
  server: 'localhost',
  port: 1433,
  database: 'mydb',
  user: 'user',
  password: 'password',
})

// Individual parameters with schemaName
const store5 = new MSSQLStore({
  id: 'mssql-storage-4',
  server: 'localhost',
  port: 1433,
  database: 'mydb',
  user: 'user',
  password: 'password',
  schemaName: 'custom_schema', // optional
})

Additional notes

Schema Management

The storage implementation handles schema creation and updates automatically. It creates the following tables:

• mastra_workflow_snapshot: Stores workflow state and execution data
• mastra_evals: Stores evaluation results and metadata
• mastra_threads: Stores conversation threads
• mastra_messages: Stores individual messages
• mastra_traces: Stores telemetry and tracing data
• mastra_scorers: Stores scoring and evaluation data
• mastra_resources: Stores resource working memory data

Initialization

When you pass storage to the Mastra class, init() is called automatically before any storage operation:

import { Mastra } from '@mastra/core'
import { MSSQLStore } from '@mastra/mssql'

const storage = new MSSQLStore({
  connectionString: process.env.DATABASE_URL,
})

const mastra = new Mastra({
  storage, // init() is called automatically
})

If you're using storage directly without Mastra, you must call init() explicitly to create the tables:

import { MSSQLStore } from '@mastra/mssql'

const storage = new MSSQLStore({
  id: 'mssql-storage',
  connectionString: process.env.DATABASE_URL,
})

// Required when using storage directly
await storage.init()

// Access domain-specific stores via getStore()
const memoryStore = await storage.getStore('memory')
const thread = await memoryStore?.getThreadById({ threadId: '...' })

:::warning If init() isn't called, tables won't be created and storage operations will fail silently or throw errors. :::

Direct Database and Pool Access

MSSQLStore exposes the mssql connection pool as public fields:

store.pool // mssql connection pool instance

This enables direct queries and custom transaction management. When using these fields:

• You are responsible for proper connection and transaction handling.
• Closing the store (store.close()) will destroy the associated connection pool.
• Direct access bypasses any additional logic or validation provided by MSSQLStore methods.

This approach is intended for advanced scenarios where low-level access is required.