{"Entry":{"collection":"sql","key":"drop-access-method","name":"DROP ACCESS METHOD","aliases":["drop-access-method"],"metadata":{"aliases":["drop-access-method"],"changed_in":[],"changes":[{"from":"9.5","purpose_changed":false,"renamed":null,"sections":{"added":[],"changed":[],"removed":[]},"status":"added","synopsis":null,"to":"9.6"},{"from":"11","purpose_changed":false,"renamed":null,"sections":{"added":[],"changed":["parameters"],"removed":[]},"status":"changed","synopsis":null,"to":"12"},{"from":"16","purpose_changed":false,"renamed":null,"sections":{"added":[],"changed":["parameters"],"removed":[]},"status":"changed","synopsis":null,"to":"17"},{"from":"18","purpose_changed":false,"renamed":null,"sections":{"added":[],"changed":["parameters"],"removed":[]},"status":"changed","synopsis":null,"to":"19"}],"content_hash":"c94362f8253825797ad1ca799eaaca6a53294e35b24c7dc3c5a7c7e42f415ae2","editorial":{},"first_version":"9.6","group":"extension","imported_at":"2026-09-30T17:43:38.499414+08:00","last_version":"20","name":"DROP ACCESS METHOD","object":"ACCESS METHOD","position":7002,"present_in":["9.6","10","11","12","13","14","15","16","17","18","19","20"],"purpose":"remove an access method","purpose_zh":"","related":["create-access-method"],"slug":"drop-access-method","source_rev":"a709ab85","synopsis":"DROP ACCESS METHOD [ IF EXISTS ] name [ CASCADE | RESTRICT ]","verb":"DROP"}},"Definition":{"Collection":"sql","Key":"drop-access-method","SourceDatabase":"center","Version":"18","SourceTable":"sqlcmd","SourceKey":"drop-access-method","SourceRevision":"a709ab85","Facts":{"anchor":"SQL-DROP-ACCESS-METHOD","file":"sql-drop-access-method.html","lang":"en","name":"DROP ACCESS METHOD","purpose":"remove an access method","purpose_zh":"","related":["create-access-method"],"sections":[{"html":"\u003cp\u003e\u003ccode class=\"command\"\u003eDROP ACCESS METHOD\u003c/code\u003e removes an existing access method. Only superusers can drop access methods.\u003c/p\u003e","key":"description","title":"Description"},{"html":"\u003cdiv class=\"variablelist\"\u003e\u003cdl class=\"variablelist\"\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eIF EXISTS\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003eDo not throw an error if the access method does not exist. A notice is issued in this case.\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003cem class=\"replaceable\"\u003e\u003ccode\u003ename\u003c/code\u003e\u003c/em\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003eThe name of an existing access method.\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eCASCADE\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003eAutomatically drop objects that depend on the access method (such as operator classes, operator families, and indexes), and in turn all objects that depend on those objects (see \u003ca href=\"/docs/18/ddl-depend.html\" title=\"5.15. Dependency Tracking\"\u003eSection 5.15\u003c/a\u003e).\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eRESTRICT\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003eRefuse to drop the access method if any objects depend on it. This is the default.\u003c/p\u003e\u003c/dd\u003e\u003c/dl\u003e\u003c/div\u003e","key":"parameters","title":"Parameters"},{"html":"\u003cp\u003eDrop the access method \u003ccode class=\"literal\"\u003eheptree\u003c/code\u003e:\u003c/p\u003e\u003cpre class=\"programlisting\"\u003eDROP ACCESS METHOD heptree;\n\u003c/pre\u003e","key":"examples","title":"Examples"},{"html":"\u003cp\u003e\u003ccode class=\"command\"\u003eDROP ACCESS METHOD\u003c/code\u003e is a \u003cspan class=\"productname\"\u003ePostgreSQL\u003c/span\u003e extension.\u003c/p\u003e","key":"compatibility","title":"Compatibility"},{"html":"\u003cspan class=\"simplelist\"\u003e\u003ca href=\"/wiki/sql/create-access-method/?v=18\" title=\"CREATE ACCESS METHOD\"\u003e\u003cspan class=\"refentrytitle\"\u003eCREATE ACCESS METHOD\u003c/span\u003e\u003c/a\u003e\u003c/span\u003e","key":"see_also","title":"See Also"}],"sections_same_as":"","slug":"18","synopsis_html":"DROP ACCESS METHOD [ IF EXISTS ] \u003cem class=\"replaceable\"\u003e\u003ccode\u003ename\u003c/code\u003e\u003c/em\u003e [ CASCADE | RESTRICT ]","synopsis_text":"DROP ACCESS METHOD [ IF EXISTS ] name [ CASCADE | RESTRICT ]"},"ManualEvidence":{},"MeasuredEvidence":{}},"Text":{"Collection":"sql","Key":"drop-access-method","SourceDatabase":"pgweb","Version":"18","Locale":"zh-Hans","Title":"DROP ACCESS METHOD","Summary":"移除一个访问方法","BodyHTML":"\u003cpre\u003eDROP ACCESS METHOD [ IF EXISTS ] name [ CASCADE | RESTRICT ]\u003c/pre\u003e\u003csection\u003e\u003ch2\u003e描述\u003c/h2\u003e\u003cp\u003e\u003ccode\u003eDROP ACCESS METHOD\u003c/code\u003e删除一个现有访问方法。只有超级用户才能删除访问方法。\u003c/p\u003e\u003c/section\u003e\u003csection\u003e\u003ch2\u003e参数\u003c/h2\u003e\u003cdiv\u003e\u003cdl\u003e\u003cdt\u003e\u003cspan\u003e\u003ccode\u003eIF EXISTS\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e如果该访问方法不存在，则不要抛出错误。这种情况下会发出一个提示。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan\u003e\u003cem\u003e\u003ccode\u003ename\u003c/code\u003e\u003c/em\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e现有访问方法的名称。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan\u003e\u003ccode\u003eCASCADE\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e自动删除依赖于该访问方法的对象（例如操作符类、操作符族和索引），以及进一步依赖于这些对象的所有对象（参见\u003ca href=\"/docs/18/ddl-depend.html\" rel=\"nofollow\"\u003e第 5.15 节\u003c/a\u003e）。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan\u003e\u003ccode\u003eRESTRICT\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e如果有任何对象依赖于该访问方法，则拒绝删除它。这是默认值。\u003c/p\u003e\u003c/dd\u003e\u003c/dl\u003e\u003c/div\u003e\u003c/section\u003e\u003csection\u003e\u003ch2\u003e示例\u003c/h2\u003e\u003cp\u003e删除访问方法\u003ccode\u003eheptree\u003c/code\u003e：\u003c/p\u003e\u003cpre\u003eDROP ACCESS METHOD heptree;\n\u003c/pre\u003e\u003c/section\u003e\u003csection\u003e\u003ch2\u003e兼容性\u003c/h2\u003e\u003cp\u003e\u003ccode\u003eDROP ACCESS METHOD\u003c/code\u003e是一种\u003cspan\u003ePostgreSQL\u003c/span\u003e扩展。\u003c/p\u003e\u003c/section\u003e\u003csection\u003e\u003ch2\u003e另见\u003c/h2\u003e\u003cspan\u003e\u003ca href=\"/wiki/sql/create-access-method/?v=18\" title=\"CREATE ACCESS METHOD\" rel=\"nofollow\"\u003e\u003cspan\u003eCREATE ACCESS METHOD\u003c/span\u003e\u003c/a\u003e\u003c/span\u003e\u003c/section\u003e","SourceRevision":"1b5ca64c","ContentHash":"2433b9e0930be848beb506a58dabf6253c143a7c83229e645ecd1968fae19528","Payload":{"purpose_zh":"移除一个访问方法","sections":[{"html":"\u003cp\u003e\u003ccode class=\"command\"\u003eDROP ACCESS METHOD\u003c/code\u003e删除一个现有访问方法。只有超级用户才能删除访问方法。\u003c/p\u003e","key":"description","title":"描述"},{"html":"\u003cdiv class=\"variablelist\"\u003e\u003cdl class=\"variablelist\"\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eIF EXISTS\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e如果该访问方法不存在，则不要抛出错误。这种情况下会发出一个提示。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003cem class=\"replaceable\"\u003e\u003ccode\u003ename\u003c/code\u003e\u003c/em\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e现有访问方法的名称。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eCASCADE\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e自动删除依赖于该访问方法的对象（例如操作符类、操作符族和索引），以及进一步依赖于这些对象的所有对象（参见\u003ca href=\"/docs/18/ddl-depend.html\" title=\"5.15. 依赖跟踪\"\u003e第 5.15 节\u003c/a\u003e）。\u003c/p\u003e\u003c/dd\u003e\u003cdt\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003eRESTRICT\u003c/code\u003e\u003c/span\u003e\u003c/dt\u003e\u003cdd\u003e\u003cp\u003e如果有任何对象依赖于该访问方法，则拒绝删除它。这是默认值。\u003c/p\u003e\u003c/dd\u003e\u003c/dl\u003e\u003c/div\u003e","key":"parameters","title":"参数"},{"html":"\u003cp\u003e删除访问方法\u003ccode class=\"literal\"\u003eheptree\u003c/code\u003e：\u003c/p\u003e\u003cpre class=\"programlisting\"\u003eDROP ACCESS METHOD heptree;\n\u003c/pre\u003e","key":"examples","title":"示例"},{"html":"\u003cp\u003e\u003ccode class=\"command\"\u003eDROP ACCESS METHOD\u003c/code\u003e是一种\u003cspan class=\"productname\"\u003ePostgreSQL\u003c/span\u003e扩展。\u003c/p\u003e","key":"compatibility","title":"兼容性"},{"html":"\u003cspan class=\"simplelist\"\u003e\u003ca href=\"/wiki/sql/create-access-method/?v=18\" title=\"CREATE ACCESS METHOD\"\u003e\u003cspan class=\"refentrytitle\"\u003eCREATE ACCESS METHOD\u003c/span\u003e\u003c/a\u003e\u003c/span\u003e","key":"see_also","title":"另见"}],"sections_same_as":"","synopsis_html":"DROP ACCESS METHOD [ IF EXISTS ] \u003cem class=\"replaceable\"\u003e\u003ccode\u003ename\u003c/code\u003e\u003c/em\u003e [ CASCADE | RESTRICT ]","synopsis_text":"DROP ACCESS METHOD [ IF EXISTS ] name [ CASCADE | RESTRICT ]"}},"RequestedLocale":"zh-Hans","Fallback":false,"Versions":["10","11","12","13","14","15","16","17","18","19","20","9.6"],"Locales":["en","zh-Hans"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}