# Batch Queries
Execute multiple GraphQL operations in a single HTTP request.
## Usage
Send an array of operations:
```bash
curl -X POST http://localhost:8888/graphql \
-H "Content-Type: application/json" \
-d '[
{"query": "{ users { id name } }"},
{"query": "{ products { upc price } }"},
{"query": "mutation { createUser(input: {name: \"Alice\"}) { id } }"}
]'
```
## Response Format
Returns an array of responses in the same order:
```json
[
{"data": {"users": [{"id": "1", "name": "Bob"}]}},
{"data": {"products": [{"upc": "123", "price": 99}]}},
{"data": {"createUser": {"id": "2"}}}
]
```
## Benefits
- Reduces HTTP overhead (one connection, one request)
- Atomic execution perception
- Ideal for initial page loads
## Considerations
- Operations execute concurrently (not sequentially)
- Mutations don't wait for previous queries
- Total response size is sum of all responses
## Error Handling
Errors are returned per-operation:
```json
[
{"data": {"users": [{"id": "1"}]}},
{"errors": [{"message": "Product not found"}]},
{"data": {"createUser": {"id": "2"}}}
]
```
## Client Example
```javascript
const batchQuery = async (queries) => {
const response = await fetch('http://localhost:8888/graphql', {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify(queries),
});
return response.json();
};
const results = await batchQuery([
{ query: '{ users { id } }' },
{ query: '{ products { upc } }' },
]);
```