> ## Documentation Index
> Fetch the complete documentation index at: https://docs.querybear.com/llms.txt
> Use this file to discover all available pages before exploring further.

# MySQL + Codex

> How to set up a secure MySQL MCP server for OpenAI's Codex CLI using QueryBear. Add to ~/.codex/config.toml. Step-by-step with read-only user and example queries.

This guide walks through connecting **MySQL** (or MariaDB) to **Codex** (OpenAI's terminal coding agent) using QueryBear's managed MCP server.

## What you'll need

* A QueryBear account ([sign up free](https://querybear.com/signup))
* A MySQL or MariaDB database (5.7+ / 10.x+)
* Codex CLI installed

## Step 1: Create a read-only MySQL user

```sql theme={null}
CREATE USER 'querybear'@'%' IDENTIFIED BY 'choose-a-strong-one';
GRANT SELECT ON your_db.* TO 'querybear'@'%';
GRANT SHOW VIEW ON your_db.* TO 'querybear'@'%';
FLUSH PRIVILEGES;
```

## Step 2: Add the connection to QueryBear

[Dashboard](https://querybear.com/dashboard) → **Connections** → **New connection** → **MySQL**, with the credentials from Step 1.

## Step 3: Add QueryBear to Codex

`~/.codex/config.toml`:

```toml theme={null}
[mcp_servers.querybear]
type = "http"
url = "https://mcp.querybear.com/mcp"
```

Restart the Codex CLI.

## Step 4: Authorize and verify

Start a Codex session. First tool call opens OAuth in browser.

> *"What QueryBear tools do you have? List my connections."*

## Try it

> *"In our MySQL DB, find the orders that had a refund processed in the last 7 days. Include order id, customer, refund amount, and reason."*

Codex calls `get_schema`, joins `orders` and `refunds`, and returns the result.

## MySQL + Codex gotchas

* **TOML typos silently disable the server.** If `querybear` doesn't appear in the tool list, re-check the TOML block.
* **Restart Codex CLI fully** after editing config — it caches MCP discovery on startup.
* **Multi-statement and stored procedure calls are blocked.** Allow-list specific procedures per connection if needed.
* **Name the connection** in your prompt (*"using the prod connection..."*) to skip `list_connections`.

## Related

* [MySQL MCP server](/databases/mysql) — MySQL-specific deep dive
* [Codex client](/clients/codex) — Codex overview
* [Security model](/features/security) — what the gateway protects against