{"Entry":{"collection":"relopts","key":"btree-deduplicate-items","name":"deduplicate_items","aliases":["btree.deduplicate_items"],"metadata":{"aliases":["btree.deduplicate_items"],"category":"B-tree indexes","content_hash":"609d50785f79e19cc923b444ea4cd0ea130253ba592fe34c60ef49a29237c5b3","imported_at":"2026-09-30T17:44:22.129848+08:00","name":"deduplicate_items","name_zh":"deduplicate_items","slug":"btree-deduplicate-items","summary":"Controls usage of the B-tree deduplication technique described in Section 65.1.4.3 . Set to ON or OFF to enable or disable the optimization. (Alternative spellings of ON and OFF are allowed as described in Section 19.1 .) The default is ON ."}},"Definition":{"Collection":"relopts","Key":"btree-deduplicate-items","SourceDatabase":"center","Version":"18","SourceTable":"relopt","SourceKey":"btree-deduplicate-items","SourceRevision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744","Facts":{"description":["Controls usage of the B-tree deduplication technique described in Section 65.1.4.3 . Set to ON or OFF to enable or disable the optimization. (Alternative spellings of ON and OFF are allowed as described in Section 19.1 .) The default is ON .","Turning deduplicate_items off via ALTER INDEX prevents future insertions from triggering deduplication, but does not in itself make existing posting list tuples use the standard tuple representation."],"facts":[{"label":"Applies to","value":"B-tree indexes"},{"label":"Value type","value":"boolean"},{"label":"Default","value":"ON"}],"related":[{"label":"CREATE INDEX","url":"/wiki/sql/create-index/?v=18"}],"release":{"channel":"stable","label":"18.6","major":"18","ref":"Local English manual 18.6","revision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744"},"sections":[{"paragraphs":["This entry applies to B-tree indexes. Set it with CREATE INDEX WITH or ALTER INDEX SET. Read defaults and behavior for this specific access method."],"title":"Index access method"}],"signature":"WITH (deduplicate_items = value)","sources":[{"label":"PostgreSQL 18 English manual","path":"sql-createindex.html","sha256":"6aa00da55815d13d0355dd25cb1cdb603fa36964993f164d1b6f486011282580","url":"/docs/18/sql-createindex.html#INDEX-RELOPTION-DEDUPLICATE-ITEMS"}]},"ManualEvidence":{"release":{"channel":"stable","label":"18.6","major":"18","ref":"Local English manual 18.6","revision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744"},"sources":[{"label":"PostgreSQL 18 English manual","path":"sql-createindex.html","sha256":"6aa00da55815d13d0355dd25cb1cdb603fa36964993f164d1b6f486011282580","url":"/docs/18/sql-createindex.html#INDEX-RELOPTION-DEDUPLICATE-ITEMS"}]},"MeasuredEvidence":{}},"Text":{"Collection":"relopts","Key":"btree-deduplicate-items","SourceDatabase":"center","Version":"18","Locale":"en","Title":"deduplicate_items","Summary":"Controls usage of the B-tree deduplication technique described in Section 65.1.4.3 . Set to ON or OFF to enable or disable the optimization. (Alternative spellings of ON and OFF are allowed as described in Section 19.1 .) The default is ON .\nTurning deduplicate_items off via ALTER INDEX prevents future insertions from triggering deduplication, but does not in itself make existing posting list tuples use the standard tuple representation.","BodyHTML":"\u003cp\u003eControls usage of the B-tree deduplication technique described in Section 65.1.4.3 . Set to ON or OFF to enable or disable the optimization. (Alternative spellings of ON and OFF are allowed as described in Section 19.1 .) The default is ON .\nTurning deduplicate_items off via ALTER INDEX prevents future insertions from triggering deduplication, but does not in itself make existing posting list tuples use the standard tuple representation.\u003c/p\u003e","SourceRevision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744","ContentHash":"20e22a121e769f4cbb52609b71f000acd4831d8f30db0fba571cc8b0c1df4547","Payload":{"description":["Controls usage of the B-tree deduplication technique described in Section 65.1.4.3 . Set to ON or OFF to enable or disable the optimization. (Alternative spellings of ON and OFF are allowed as described in Section 19.1 .) The default is ON .","Turning deduplicate_items off via ALTER INDEX prevents future insertions from triggering deduplication, but does not in itself make existing posting list tuples use the standard tuple representation."],"related":[{"label":"CREATE INDEX","url":"/wiki/sql/create-index/?v=18"}],"sections":[{"paragraphs":["This entry applies to B-tree indexes. Set it with CREATE INDEX WITH or ALTER INDEX SET. Read defaults and behavior for this specific access method."],"title":"Index access method"}]}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["13","14","15","16","17","18","19","20"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}