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By removing the infrequently-accessed value slices from the hash table record, it improves cache locality. The Unique Strings Self-aligned Region (USSR) accelerates handling frequently occurring strings, which are widespread in real-world data sets, by creating an on-the-fly dictionary of the most frequent strings. This allows executing many string operations with integer logic and reduces memory pressure.<\/jats:p>\n We integrated these techniques into Vectorwise. On the TPC-H benchmark, our approach reduces peak memory consumption by 2-4\u00d7 and improves performance by up to 1.5\u00d7. On a real-world BI workload, we measured a 2\u00d7 improvement in performance and in micro-benchmarks we observed speedups of up to 25\u00d7.<\/jats:p>","DOI":"10.1145\/3471485.3471500","type":"journal-article","created":{"date-parts":[[2021,6,18]],"date-time":"2021-06-18T05:22:06Z","timestamp":1623993726000},"page":"60-67","update-policy":"http:\/\/dx.doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimistically Compressed Hash Tables & Strings in theUSSR"],"prefix":"10.1145","volume":"50","author":[{"given":"Tim","family":"Gubner","sequence":"first","affiliation":[{"name":"CWI"}]},{"given":"Viktor","family":"Leis","sequence":"additional","affiliation":[{"name":"FSU Jena"}]},{"given":"Peter","family":"Boncz","sequence":"additional","affiliation":[{"name":"CWI"}]}],"member":"320","published-online":{"date-parts":[[2021,6,17]]},"reference":[{"key":"e_1_2_1_1_1","unstructured":"https:\/\/public.tableau.com. https:\/\/public.tableau.com."},{"key":"e_1_2_1_2_1","unstructured":"https:\/\/github.com\/cwida\/public_bi_benchmark. https:\/\/github.com\/cwida\/public_bi_benchmark."},{"key":"e_1_2_1_3_1","doi-asserted-by":"publisher","DOI":"10.1145\/1142473.1142548"},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1109\/ICDE.2013.6544839"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.14778\/2735496.2735499"},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.1145\/1559845.1559877"},{"key":"e_1_2_1_7_1","first-page":"103","volume-title":"TPCTC","author":"Boncz P.","year":"2017"},{"key":"e_1_2_1_8_1","first-page":"225","volume-title":"CIDR","author":"Boncz P.","year":"2005"},{"key":"e_1_2_1_10_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-32627-1_10"},{"key":"e_1_2_1_11_1","doi-asserted-by":"publisher","DOI":"10.1145\/2094114.2094126"},{"key":"e_1_2_1_12_1","doi-asserted-by":"publisher","DOI":"10.1145\/3183713.3196911"},{"key":"e_1_2_1_13_1","doi-asserted-by":"publisher","DOI":"10.1145\/2882903.2882957"},{"key":"e_1_2_1_14_1","doi-asserted-by":"publisher","DOI":"10.1145\/2882903.2882925"},{"key":"e_1_2_1_15_1","doi-asserted-by":"publisher","DOI":"10.1145\/2463676.2463708"},{"key":"e_1_2_1_16_1","doi-asserted-by":"publisher","DOI":"10.14778\/2733004.2733008"},{"key":"e_1_2_1_17_1","doi-asserted-by":"publisher","DOI":"10.1145\/2463676.2465322"},{"key":"e_1_2_1_18_1","first-page":"283","volume-title":"EDBT","author":"M\u00a8uller I.","year":"2014"},{"key":"e_1_2_1_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jalgor.2003.12.002"},{"key":"e_1_2_1_20_1","doi-asserted-by":"publisher","DOI":"10.5555\/3199517.3199518"},{"key":"e_1_2_1_21_1","doi-asserted-by":"publisher","DOI":"10.14778\/2536222.2536233"},{"key":"e_1_2_1_22_1","doi-asserted-by":"publisher","DOI":"10.1145\/2882903.2882917"},{"key":"e_1_2_1_23_1","doi-asserted-by":"publisher","DOI":"10.5555\/645920.758363"},{"key":"e_1_2_1_24_1","doi-asserted-by":"publisher","DOI":"10.1145\/3209950.3209952"},{"key":"e_1_2_1_25_1","doi-asserted-by":"publisher","DOI":"10.14778\/1687627.1687671"},{"key":"e_1_2_1_26_1","doi-asserted-by":"publisher","DOI":"10.1109\/ICDE.2006.150"},{"key":"e_1_2_1_27_1","doi-asserted-by":"publisher","DOI":"10.1145\/1457150.1457160"}],"container-title":["ACM SIGMOD Record"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dl.acm.org\/doi\/pdf\/10.1145\/3471485.3471500","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,1,2]],"date-time":"2023-01-02T00:20:10Z","timestamp":1672618810000},"score":1,"resource":{"primary":{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3471485.3471500"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,15]]},"references-count":26,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2021,6,15]]}},"alternative-id":["10.1145\/3471485.3471500"],"URL":"http:\/\/dx.doi.org\/10.1145\/3471485.3471500","relation":{},"ISSN":["0163-5808"],"issn-type":[{"value":"0163-5808","type":"print"}],"subject":[],"published":{"date-parts":[[2021,6,15]]},"assertion":[{"value":"2021-06-17","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}
