HTTP methods

sparqlite supports both GET and POST HTTP methods for SPARQL requests, following the SPARQL 1.1 Protocol specification.

Default methods

Each query type uses a default HTTP method:

Query type	Default method	Reason
SELECT	GET	Read operation, cacheable
ASK	GET	Read operation, cacheable
CONSTRUCT	GET	Read operation, cacheable
DESCRIBE	GET	Read operation, cacheable
UPDATE	POST	Write operation (required by spec)

GET requests pass the query as a URL parameter (?query=...). POST requests pass the query in the request body as form-encoded data.

Overriding the default method

All read query methods accept a method keyword argument:

from sparqlite import SPARQLClient

with SPARQLClient("https://opencitations.net/meta/sparql") as client:
    # Use POST for a long SELECT query that may exceed URL length limits
    result = client.query(long_query, method="POST")

    # Use POST for ASK
    exists = client.ask(query, method="POST")

    # Use POST for CONSTRUCT
    triples = client.construct(query, method="POST")

    # Use POST for DESCRIBE
    data = client.describe(query, method="POST")

Note

The update() method always uses POST. The SPARQL 1.1 Protocol specification requires POST for update operations.

When to use POST for read queries

Use method="POST" when:

• The query string is very long and may exceed URL length limits (typically 2000-8000 characters depending on the server)
• You want to avoid caching of results

with SPARQLClient("https://opencitations.net/meta/sparql") as client:
    long_query = "SELECT * WHERE { " + " UNION ".join(
        f"{{ ?s <http://example.org/p{i}> ?o }}" for i in range(100)
    ) + " }"

    # POST avoids URL length issues
    result = client.query(long_query, method="POST")