# MySQL Client

Execute SQL queries and statements against MySQL databases with full type safety and runtime validation.

## Methods

| Method                                      | Description                                                                |
| ------------------------------------------- | -------------------------------------------------------------------------- |
| `query<T>(sql, schema, params?, metadata?)` | Execute a SELECT query and return validated, typed results                 |
| `execute(sql, params?, metadata?)`          | Execute a statement (INSERT, UPDATE, DELETE) and return affected row count |

## Usage

### Basic Query with Schema Validation

```typescript
import { api, z, mysql } from "@superblocksteam/sdk-api";

// Integration ID from the integrations panel
const PROD_MYSQL = "a1b2c3d4-5678-90ab-cdef-mysql0000001";

const UserSchema = z.object({
  id: z.number(),
  name: z.string(),
  email: z.string().email(),
  created_at: z.string(),
});

export default api({
  integrations: {
    mysql: mysql(PROD_MYSQL),
  },
  name: "MySQLExample",
  input: z.object({
    status: z.string(),
  }),
  output: z.object({
    users: z.array(UserSchema),
  }),
  async run(ctx, { status }) {
    const users = await ctx.integrations.mysql.query(
      "SELECT id, name, email, created_at FROM users WHERE status = ?",
      UserSchema,
      [status],
    );

    return { users };
  },
});
```

### Executing INSERT, UPDATE, DELETE Statements

```typescript
// INSERT
await ctx.integrations.mysql.execute(
  "INSERT INTO users (name, email) VALUES (?, ?)",
  ["John Doe", "john@example.com"],
);

// UPDATE
const updateResult = await ctx.integrations.mysql.execute(
  "UPDATE users SET last_login = NOW() WHERE id = ?",
  [userId],
);
console.log(`Updated ${updateResult.rowCount} rows`);

// DELETE
const deleteResult = await ctx.integrations.mysql.execute(
  "DELETE FROM sessions WHERE expires_at < NOW()",
);
console.log(`Deleted ${deleteResult.rowCount} expired sessions`);
```

### Query with JOIN

```typescript
const OrderWithCustomerSchema = z.object({
  order_id: z.number(),
  order_total: z.string(),
  customer_name: z.string(),
  customer_email: z.string().email(),
});

const orders = await ctx.integrations.mysql.query(
  `SELECT
    o.id as order_id,
    o.total as order_total,
    c.name as customer_name,
    c.email as customer_email
  FROM orders o
  JOIN customers c ON o.customer_id = c.id
  WHERE o.status = ?`,
  OrderWithCustomerSchema,
  ["pending"],
);
```

## Trace Metadata

All methods accept an optional `metadata` parameter as the last argument for diagnostics labeling. See the [root SDK README](../../../README.md#trace-metadata) for details.

## Common Pitfalls

### BIGINT Values Returned as Strings

MySQL `BIGINT` columns may be returned as strings to preserve precision:

```typescript
// CORRECT - Handle as strings or coerce
const schema = z.object({
  id: z.coerce.number(),
  count: z.coerce.number(),
});
```

### DECIMAL Values Returned as Strings

```typescript
// For a column: price DECIMAL(10,2)
const schema = z.object({
  price: z.string().transform((val) => parseFloat(val)),
});
```

### Schema Parameter is Required

```typescript
// WRONG - Missing schema
const users = await ctx.integrations.mysql.query("SELECT * FROM users");

// CORRECT - Schema is required
const users = await ctx.integrations.mysql.query(
  "SELECT * FROM users",
  UserSchema,
);
```

### NULL Handling

```typescript
const schema = z.object({
  name: z.string(),
  bio: z.string().nullable(), // Column can be NULL
});
```

## Error Handling

```typescript
import { QueryValidationError } from "@superblocksteam/sdk-api";

try {
  const users = await ctx.integrations.mysql.query(
    "SELECT * FROM users",
    UserSchema,
  );
} catch (error) {
  if (error instanceof QueryValidationError) {
    console.error("Row index:", error.details.rowIndex);
    console.error("Validation errors:", error.details.errors);
  }
}
```

## API Reference

- [MySQL Documentation](https://dev.mysql.com/doc/)
- [MySQL Data Types](https://dev.mysql.com/doc/refman/8.0/en/data-types.html)