{"Entry":{"collection":"relopts","key":"table-autovacuum-multixact-freeze-max-age","name":"autovacuum_multixact_freeze_max_age","aliases":["table.autovacuum_multixact_freeze_max_age"],"metadata":{"aliases":["table.autovacuum_multixact_freeze_max_age"],"category":"Tables and materialized views","content_hash":"6a7790d03bc1fe48873877a769bc4afa30d91652fb921873b89c9ff8ca91e3ae","imported_at":"2026-09-30T17:44:22.195964+08:00","name":"autovacuum_multixact_freeze_max_age","name_zh":"autovacuum_multixact_freeze_max_age","slug":"table-autovacuum-multixact-freeze-max-age","summary":"Per-table value for autovacuum_multixact_freeze_max_age parameter. Note that autovacuum will ignore per-table autovacuum_multixact_freeze_max_age parameters that are larger than the system-wide setting (it can only be set smaller)."}},"Definition":{"Collection":"relopts","Key":"table-autovacuum-multixact-freeze-max-age","SourceDatabase":"center","Version":"18","SourceTable":"relopt","SourceKey":"table-autovacuum-multixact-freeze-max-age","SourceRevision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744","Facts":{"description":["Per-table value for autovacuum_multixact_freeze_max_age parameter. Note that autovacuum will ignore per-table autovacuum_multixact_freeze_max_age parameters that are larger than the system-wide setting (it can only be set smaller)."],"facts":[{"label":"Applies to","value":"Tables and materialized views"},{"label":"Value type","value":"integer"}],"related":[{"label":"Global parameter autovacuum_multixact_freeze_max_age","url":"/wiki/guc/autovacuum_multixact_freeze_max_age/?v=18"},{"label":"CREATE TABLE","url":"/wiki/sql/create-table/?v=18"}],"release":{"channel":"stable","label":"18.6","major":"18","ref":"Local English manual 18.6","revision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744"},"sections":[{"paragraphs":["This relation-level setting applies to the table or materialized view. Any corresponding global parameter has a separate entry."],"title":"Scope"},{"paragraphs":["The WITH clause can specify storage parameters for tables, and for indexes associated with a UNIQUE , PRIMARY KEY , or EXCLUDE constraint. Storage parameters for indexes are documented in CREATE INDEX . The storage parameters currently available for tables are listed below. For many of these parameters, as shown, there is an additional parameter with the same name prefixed with toast. , which controls the behavior of the table's secondary TOAST table, if any (see Section 66.2 for more information about TOAST). If a table parameter value is set and the equivalent toast. parameter is not, the TOAST table will use the table's parameter value. Specifying these parameters for partitioned tables is not supported, but you may specify them for individual leaf partitions."],"title":"Common table storage rules"},{"paragraphs":["This clause specifies optional storage parameters for the new materialized view; see Storage Parameters in the CREATE TABLE documentation for more information. All parameters supported for CREATE TABLE are also supported for CREATE MATERIALIZED VIEW . See CREATE TABLE for more information."],"title":"Materialized views"},{"paragraphs":["The following same-version GUC definition explains its purpose and units. Global defaults and activation rules describe the GUC; the relation-option override rules remain those above.","Specifies the maximum age (in multixacts) that a table's pg_class . relminmxid field can attain before a VACUUM operation is forced to prevent multixact ID wraparound within the table. Note that the system will launch autovacuum processes to prevent wraparound even when autovacuum is otherwise disabled.","Vacuuming multixacts also allows removal of old files from the pg_multixact/members and pg_multixact/offsets subdirectories, which is why the default is a relatively low 400 million multixacts. This parameter can only be set at server start, but the setting can be reduced for individual tables by changing table storage parameters. For more information see Section 24.1.5.1 ."],"title":"Related global parameter: autovacuum_multixact_freeze_max_age"}],"signature":"WITH (autovacuum_multixact_freeze_max_age = value)","sources":[{"label":"PostgreSQL 18 English manual","path":"sql-createtable.html","sha256":"b4d703391fe1102d0e02bd6769bef928513eb7a5542f38f7448fc77fe69e0d5b","url":"/docs/18/sql-createtable.html#RELOPTION-AUTOVACUUM-MULTIXACT-FREEZE-MAX-AGE"},{"label":"Related global parameter: autovacuum_multixact_freeze_max_age","path":"runtime-config-vacuum.html","sha256":"7047f1fa9138b97f1812532f8a905fa7479451dfd64655e029a7d387b20b22e4","url":"/docs/18/runtime-config-vacuum.html#GUC-AUTOVACUUM-MULTIXACT-FREEZE-MAX-AGE"},{"label":"PostgreSQL 18 English manual","path":"sql-creatematerializedview.html","sha256":"bd8a6710c9f133afee191eb0ec345ef8c54bb54db2242621d8cb683c783a8b18","url":"/docs/18/sql-creatematerializedview.html"}]},"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-createtable.html","sha256":"b4d703391fe1102d0e02bd6769bef928513eb7a5542f38f7448fc77fe69e0d5b","url":"/docs/18/sql-createtable.html#RELOPTION-AUTOVACUUM-MULTIXACT-FREEZE-MAX-AGE"},{"label":"Related global parameter: autovacuum_multixact_freeze_max_age","path":"runtime-config-vacuum.html","sha256":"7047f1fa9138b97f1812532f8a905fa7479451dfd64655e029a7d387b20b22e4","url":"/docs/18/runtime-config-vacuum.html#GUC-AUTOVACUUM-MULTIXACT-FREEZE-MAX-AGE"},{"label":"PostgreSQL 18 English manual","path":"sql-creatematerializedview.html","sha256":"bd8a6710c9f133afee191eb0ec345ef8c54bb54db2242621d8cb683c783a8b18","url":"/docs/18/sql-creatematerializedview.html"}]},"MeasuredEvidence":{}},"Text":{"Collection":"relopts","Key":"table-autovacuum-multixact-freeze-max-age","SourceDatabase":"center","Version":"18","Locale":"en","Title":"autovacuum_multixact_freeze_max_age","Summary":"Per-table value for autovacuum_multixact_freeze_max_age parameter. Note that autovacuum will ignore per-table autovacuum_multixact_freeze_max_age parameters that are larger than the system-wide setting (it can only be set smaller).","BodyHTML":"\u003cp\u003ePer-table value for autovacuum_multixact_freeze_max_age parameter. Note that autovacuum will ignore per-table autovacuum_multixact_freeze_max_age parameters that are larger than the system-wide setting (it can only be set smaller).\u003c/p\u003e","SourceRevision":"eb6c2292fdf28e1b4635ab478eec3919411cdf4a6c07553387870e26201f3744","ContentHash":"9220853d09b511bb2bd397da38fb0e83d0c212e0a1f095bbee5802d5c138b525","Payload":{"description":["Per-table value for autovacuum_multixact_freeze_max_age parameter. Note that autovacuum will ignore per-table autovacuum_multixact_freeze_max_age parameters that are larger than the system-wide setting (it can only be set smaller)."],"related":[{"label":"Global parameter autovacuum_multixact_freeze_max_age","url":"/wiki/guc/autovacuum_multixact_freeze_max_age/?v=18"},{"label":"CREATE TABLE","url":"/wiki/sql/create-table/?v=18"}],"sections":[{"paragraphs":["This relation-level setting applies to the table or materialized view. Any corresponding global parameter has a separate entry."],"title":"Scope"},{"paragraphs":["The WITH clause can specify storage parameters for tables, and for indexes associated with a UNIQUE , PRIMARY KEY , or EXCLUDE constraint. Storage parameters for indexes are documented in CREATE INDEX . The storage parameters currently available for tables are listed below. For many of these parameters, as shown, there is an additional parameter with the same name prefixed with toast. , which controls the behavior of the table's secondary TOAST table, if any (see Section 66.2 for more information about TOAST). If a table parameter value is set and the equivalent toast. parameter is not, the TOAST table will use the table's parameter value. Specifying these parameters for partitioned tables is not supported, but you may specify them for individual leaf partitions."],"title":"Common table storage rules"},{"paragraphs":["This clause specifies optional storage parameters for the new materialized view; see Storage Parameters in the CREATE TABLE documentation for more information. All parameters supported for CREATE TABLE are also supported for CREATE MATERIALIZED VIEW . See CREATE TABLE for more information."],"title":"Materialized views"},{"paragraphs":["The following same-version GUC definition explains its purpose and units. Global defaults and activation rules describe the GUC; the relation-option override rules remain those above.","Specifies the maximum age (in multixacts) that a table's pg_class . relminmxid field can attain before a VACUUM operation is forced to prevent multixact ID wraparound within the table. Note that the system will launch autovacuum processes to prevent wraparound even when autovacuum is otherwise disabled.","Vacuuming multixacts also allows removal of old files from the pg_multixact/members and pg_multixact/offsets subdirectories, which is why the default is a relatively low 400 million multixacts. This parameter can only be set at server start, but the setting can be reduced for individual tables by changing table storage parameters. For more information see Section 24.1.5.1 ."],"title":"Related global parameter: autovacuum_multixact_freeze_max_age"}]}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["10","11","12","13","14","15","16","17","18","19","20"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}
