MySQL

DoubleDino Proxy supports native MySQL queries.

Developers can use normal MySQL SQL syntax, including:

• SELECT queries.
• Filters.
• Joins.
• Aggregations.
• Complex queries.

Queries execute against the connected MySQL database, but returned data is transformed before being returned.

Endpoint

Use:

/query

Basic query

curl

curl -G "http://localhost:8080/query" \
  --data-urlencode "q=SELECT * FROM orders WHERE id=1" \
  -H "x-api-key: your-api-key"

Node.js / Bun

const query = "SELECT * FROM orders WHERE id=1";

const response = await fetch(
  "http://localhost:8080/query?q=" + encodeURIComponent(query),
  {
    headers: {
      "x-api-key": "your-api-key"
    }
  }
);

const data = await response.json();

console.log(data);

Python

import requests

response = requests.get(
    "http://localhost:8080/query",
    params={
        "q": "SELECT * FROM orders WHERE id=1"
    },
    headers={
        "x-api-key": "your-api-key"
    }
)

print(response.json())

Example response:

{
  "id": 1,
  "order_uid": "HDK-G98KHBGTDS",
  "status": "processing",
  "total_amount": "460.29"
}

The response keeps the original structure while sensitive values are transformed.

Debugging production issues

A common workflow is starting with a known production identifier.

Example:

Order: KLP-X60SLVTFMK

Query:

curl

curl -G "http://localhost:8080/query" \
  --data-urlencode "q=SELECT * FROM orders WHERE order_uid='KLP-X60SLVTFMK'" \
  -H "x-api-key: your-api-key"

Node.js / Bun

const query =
  "SELECT * FROM orders WHERE order_uid='KLP-X60SLVTFMK'";

const response = await fetch(
  "http://localhost:8080/query?q=" + encodeURIComponent(query),
  {
    headers: {
      "x-api-key": "your-api-key"
    }
  }
);

console.log(await response.json());

Python

import requests

query = """
SELECT *
FROM orders
WHERE order_uid='KLP-X60SLVTFMK'
"""

response = requests.get(
    "http://localhost:8080/query",
    params={
        "q": query
    },
    headers={
        "x-api-key": "your-api-key"
    }
)

print(response.json())

The query uses the real production value.

The response contains transformed values:

{
  "order_uid": "HDK-G98KHBGTDS",
  "status": "processing"
}

This allows developers to investigate real issues without exposing original production data.

Joins

Normal MySQL joins work as expected.

Example:

SELECT
  orders.id,
  orders.order_uid,
  users.email
FROM orders
JOIN users
ON users.id = orders.user_id
WHERE orders.id = 1;

The returned JSON follows the query result while sensitive values are transformed.

JSON fields

MySQL JSON fields are supported.

DoubleDino transforms nested JSON values while preserving:

• Object structure.
• Arrays.
• Data types.

Example:

Before:

{
  "customer": {
    "name": "Alice",
    "tags": [
      "vip",
      "priority"
    ]
  }
}

After:

{
  "customer": {
    "name": "Eotrl",
    "tags": [
      "vip",
      "priority"
    ]
  }
}

Preserving known expressions

If enabled by your administrator, additional expressions can be preserved per request.

Header:

x-preserve-expressions

Example:

-H "x-preserve-expressions: tracking metadata"

This requires:

DD_ALLOW_DYNAMIC_EXPRESSIONS=true

Response format

All MySQL query responses are returned as JSON.

Single row:

{
  "id": 1,
  "name": "example"
}

Multiple rows:

[
  {
    "id": 1
  },
  {
    "id": 2
  }
]

Notes

• DoubleDino does not modify MySQL data.
• Queries execute against the connected source.
• Returned values are always transformed.
• The original database remains unchanged.

Next steps

Continue with:

• MariaDB
• MongoDB
• Redis
• Logs