{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:LRABO2FGTQ3FBHM664TNVMUQI6","short_pith_number":"pith:LRABO2FG","canonical_record":{"source":{"id":"1705.07105","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.AI","submitted_at":"2017-05-19T17:33:28Z","cross_cats_sorted":[],"title_canon_sha256":"85a1bd7fc5d365ce8480e524b11f36924b9d4b5dbb26cabe1d5b1a8ad17bde0d","abstract_canon_sha256":"c70d502fa592cd07717be61dd567232889e4c15c56ca76aed787de01eac0ae34"},"schema_version":"1.0"},"canonical_sha256":"5c401768a69c36509d9ef726dab2904786d6cefdd818b0b74a2053daf880e5bd","source":{"kind":"arxiv","id":"1705.07105","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1705.07105","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"arxiv_version","alias_value":"1705.07105v1","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1705.07105","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"pith_short_12","alias_value":"LRABO2FGTQ3F","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_16","alias_value":"LRABO2FGTQ3FBHM6","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_8","alias_value":"LRABO2FG","created_at":"2026-05-18T12:31:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:LRABO2FGTQ3FBHM664TNVMUQI6","target":"record","payload":{"canonical_record":{"source":{"id":"1705.07105","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.AI","submitted_at":"2017-05-19T17:33:28Z","cross_cats_sorted":[],"title_canon_sha256":"85a1bd7fc5d365ce8480e524b11f36924b9d4b5dbb26cabe1d5b1a8ad17bde0d","abstract_canon_sha256":"c70d502fa592cd07717be61dd567232889e4c15c56ca76aed787de01eac0ae34"},"schema_version":"1.0"},"canonical_sha256":"5c401768a69c36509d9ef726dab2904786d6cefdd818b0b74a2053daf880e5bd","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:44:10.612036Z","signature_b64":"NWB0A8RrRimuA1XkOhxt7e+fEnt3N7ERp4S0rmsqOk1TjfzE2dtVEhJyD7TkltYY926g9+YXeZNXNqlntxRNBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5c401768a69c36509d9ef726dab2904786d6cefdd818b0b74a2053daf880e5bd","last_reissued_at":"2026-05-18T00:44:10.611604Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:44:10.611604Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1705.07105","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:44:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"e3t8cU7ifoRBedAk6OlJZuM3D5jLb4t73cDhsqMopfqQeOFxEv5Ymgsi0CWlCZH7luA1eg5u9HGq7JkgWRObDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T18:05:16.974420Z"},"content_sha256":"5bfe8fa0363f7a371139d3e12410f133e7a69da7f5268e43c417104b2ff8019a","schema_version":"1.0","event_id":"sha256:5bfe8fa0363f7a371139d3e12410f133e7a69da7f5268e43c417104b2ff8019a"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:LRABO2FGTQ3FBHM664TNVMUQI6","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The Bag Semantics of Ontology-Based Data Access","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.AI","authors_text":"Bernardo Cuenca Grau, Charalampos Nikolaou, Egor V. Kostylev, George Konstantinidis, Ian Horrocks, Mark Kaminski","submitted_at":"2017-05-19T17:33:28Z","abstract_excerpt":"Ontology-based data access (OBDA) is a popular approach for integrating and querying multiple data sources by means of a shared ontology. The ontology is linked to the sources using mappings, which assign views over the data to ontology predicates. Motivated by the need for OBDA systems supporting database-style aggregate queries, we propose a bag semantics for OBDA, where duplicate tuples in the views defined by the mappings are retained, as is the case in standard databases. We show that bag semantics makes conjunctive query answering in OBDA coNP-hard in data complexity. To regain tractabil"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1705.07105","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:44:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"4QR0Iz893B1/XaxrrcYZ8yhFzCIf4NmJIVR1Y4OogWZJlpqAMid3+WBIqceTLdXbCCyZ/G42+dTMfPa1iivaCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T18:05:16.974814Z"},"content_sha256":"acafae6e2f8225ead376d8246ba020949af271e36f8e93307b3adae3c6fdce67","schema_version":"1.0","event_id":"sha256:acafae6e2f8225ead376d8246ba020949af271e36f8e93307b3adae3c6fdce67"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/LRABO2FGTQ3FBHM664TNVMUQI6/bundle.json","state_url":"https://pith.science/pith/LRABO2FGTQ3FBHM664TNVMUQI6/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/LRABO2FGTQ3FBHM664TNVMUQI6/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-26T18:05:16Z","links":{"resolver":"https://pith.science/pith/LRABO2FGTQ3FBHM664TNVMUQI6","bundle":"https://pith.science/pith/LRABO2FGTQ3FBHM664TNVMUQI6/bundle.json","state":"https://pith.science/pith/LRABO2FGTQ3FBHM664TNVMUQI6/state.json","well_known_bundle":"https://pith.science/.well-known/pith/LRABO2FGTQ3FBHM664TNVMUQI6/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:LRABO2FGTQ3FBHM664TNVMUQI6","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"c70d502fa592cd07717be61dd567232889e4c15c56ca76aed787de01eac0ae34","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.AI","submitted_at":"2017-05-19T17:33:28Z","title_canon_sha256":"85a1bd7fc5d365ce8480e524b11f36924b9d4b5dbb26cabe1d5b1a8ad17bde0d"},"schema_version":"1.0","source":{"id":"1705.07105","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1705.07105","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"arxiv_version","alias_value":"1705.07105v1","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1705.07105","created_at":"2026-05-18T00:44:10Z"},{"alias_kind":"pith_short_12","alias_value":"LRABO2FGTQ3F","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_16","alias_value":"LRABO2FGTQ3FBHM6","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_8","alias_value":"LRABO2FG","created_at":"2026-05-18T12:31:28Z"}],"graph_snapshots":[{"event_id":"sha256:acafae6e2f8225ead376d8246ba020949af271e36f8e93307b3adae3c6fdce67","target":"graph","created_at":"2026-05-18T00:44:10Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Ontology-based data access (OBDA) is a popular approach for integrating and querying multiple data sources by means of a shared ontology. The ontology is linked to the sources using mappings, which assign views over the data to ontology predicates. Motivated by the need for OBDA systems supporting database-style aggregate queries, we propose a bag semantics for OBDA, where duplicate tuples in the views defined by the mappings are retained, as is the case in standard databases. We show that bag semantics makes conjunctive query answering in OBDA coNP-hard in data complexity. To regain tractabil","authors_text":"Bernardo Cuenca Grau, Charalampos Nikolaou, Egor V. Kostylev, George Konstantinidis, Ian Horrocks, Mark Kaminski","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.AI","submitted_at":"2017-05-19T17:33:28Z","title":"The Bag Semantics of Ontology-Based Data Access"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1705.07105","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:5bfe8fa0363f7a371139d3e12410f133e7a69da7f5268e43c417104b2ff8019a","target":"record","created_at":"2026-05-18T00:44:10Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"c70d502fa592cd07717be61dd567232889e4c15c56ca76aed787de01eac0ae34","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.AI","submitted_at":"2017-05-19T17:33:28Z","title_canon_sha256":"85a1bd7fc5d365ce8480e524b11f36924b9d4b5dbb26cabe1d5b1a8ad17bde0d"},"schema_version":"1.0","source":{"id":"1705.07105","kind":"arxiv","version":1}},"canonical_sha256":"5c401768a69c36509d9ef726dab2904786d6cefdd818b0b74a2053daf880e5bd","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5c401768a69c36509d9ef726dab2904786d6cefdd818b0b74a2053daf880e5bd","first_computed_at":"2026-05-18T00:44:10.611604Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:44:10.611604Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"NWB0A8RrRimuA1XkOhxt7e+fEnt3N7ERp4S0rmsqOk1TjfzE2dtVEhJyD7TkltYY926g9+YXeZNXNqlntxRNBA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:44:10.612036Z","signed_message":"canonical_sha256_bytes"},"source_id":"1705.07105","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5bfe8fa0363f7a371139d3e12410f133e7a69da7f5268e43c417104b2ff8019a","sha256:acafae6e2f8225ead376d8246ba020949af271e36f8e93307b3adae3c6fdce67"],"state_sha256":"dfe3cfc0d59dcfd9f8b3f4d21dea690288065a213f8c1af327f27a6ea6695150"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nhSVkgBgspzX43uV2PQP+F4GuRFJwLyJgfpsCIEalJ3QVAbcm6Hj0IlqMeuTJFU/fZi1XPcLNrp9rxXwJtkBAA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-26T18:05:16.977052Z","bundle_sha256":"90337040233e7736557a7868e1adbc0ef1caf7f33dacc3b4455ad08b3d1b18bf"}}