{"Entry":{"collection":"func","key":"pg-column-compression","name":"pg_column_compression","aliases":[],"metadata":{"changed_in":[],"changes":[{"descriptions_changed":false,"doc_overhaul":false,"from":"13","group_changed":null,"signatures":{"added":[],"removed":[]},"status":"added","to":"14"}],"content_hash":"68641c4dc636290cda53cea3b40ef258ad4067a3bbe6c488dc5e4bd71eb7f750","derived_content_hash":"619c93dc76e1eaabf19efaa1fd3e52bb23bf3a5a5eb51042d085bfd649597a56","documentation_refresh":{"batch":"20261113","original_source_rev":"wiki-repair-20261023:83e1932017e245680f6211d14298fa1d873604f4df493e5ca86e0bb1720de0c4","versions":{"14":"14.25","15":"15.20","16":"16.16","17":"17.12","18":"18.7","19":"19rc2"}},"first_version":"14","group":"admin","group_label":"System Administration Functions","groups":["admin"],"imported_at":"2026-09-27T17:57:29.458948+08:00","last_version":"20","name":"pg_column_compression","name_key":"pg_column_compression","position":29020,"present_in":["14","15","16","17","18","19","20"],"repair_provenance":{"original_source_revision":"b7bd9cda","receipt_sha256":"12f1d261d5dbe2979797967c8cd63fdd39ff6cb0974f37bd0505ba25a8bde2db","repair":"wiki-repair-20261023"},"signature":"pg_column_compression ( \"any\" ) → text","signature_count":1,"slug":"pg-column-compression","source_rev":"wiki-repair-20261023:83e1932017e245680f6211d14298fa1d873604f4df493e5ca86e0bb1720de0c4","summary":"Shows the compression algorithm that was used to compress an individual variable-length value.","summary_zh":""}},"Definition":{"Collection":"func","Key":"pg-column-compression","SourceDatabase":"center","Version":"18","SourceTable":"func","SourceKey":"pg-column-compression","SourceRevision":"wiki-repair-20261023:83e1932017e245680f6211d14298fa1d873604f4df493e5ca86e0bb1720de0c4","Facts":{"description":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","description_html":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e if the value is not compressed.","description_zh":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 NULL。","description_zh_html":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e。","doc":{"anchor":"FUNCTIONS-ADMIN-DBSIZE","file":"functions-admin.html","sha256":"885561d57facd49c33b44a50e320a002197d700d118784cc87d6410efadbd1f6","slug":"18"},"documentation_revision":{"inputs":[{"file":"functions-admin.html","kind":"same-version-reviewed-manual","locale":"en","sha256":"885561d57facd49c33b44a50e320a002197d700d118784cc87d6410efadbd1f6","version":"18.7"},{"file":"functions-admin.html","kind":"same-version-reviewed-manual","locale":"zh-Hans","sha256":"830e894d29fec30b7c350c915fcaed4a63b24d57f2c96150bf25fa07fb43849c","version":"18.7"}],"release":"18.7","runtime_remeasured":false,"source_revision":"pgdoc:b9f0e7232f60f380d642ac9b99226606c254b552"},"group":"admin","group_label":"系统管理函数","lang":"en","layout":"table-new","pages":["functions-admin.html"],"prose_only":false,"signatures":[{"description":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","description_html":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e if the value is not compressed.","description_zh":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 NULL。","description_zh_html":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e。","examples":[],"html":"\u003ccode class=\"function\"\u003epg_column_compression\u003c/code\u003e ( \u003ccode class=\"type\"\u003e\"any\"\u003c/code\u003e ) → \u003ccode class=\"returnvalue\"\u003etext\u003c/code\u003e","returns":"text","text":"pg_column_compression ( \"any\" ) → text","zh_from":"same-version-manual"}],"translation_provenance":{"inputs":[{"kind":"current-pgdoc-translation","path":"/Users/vonng/pgsty/pgdoc/zh/18/html/functions-admin.html","sha256":"b4fab9daceb7883fd75b32b6eb5398f2bbbfbbed5c83d1b2bf99cc8d842cdaf7"}],"kind":"same-version-pgdoc","locale":"zh-Hans","source_revision":"b1b500221dbe5437cfca004d6b04d3f6e422765d","version":"18"},"zh_from":"same-version-manual"},"ManualEvidence":{"doc":{"anchor":"FUNCTIONS-ADMIN-DBSIZE","file":"functions-admin.html","sha256":"885561d57facd49c33b44a50e320a002197d700d118784cc87d6410efadbd1f6","slug":"18"}},"MeasuredEvidence":{}},"Text":{"Collection":"func","Key":"pg-column-compression","SourceDatabase":"center","Version":"18","Locale":"en","Title":"pg_column_compression","Summary":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","BodyHTML":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode\u003eNULL\u003c/code\u003e if the value is not compressed.","SourceRevision":"wiki-repair-20261023:83e1932017e245680f6211d14298fa1d873604f4df493e5ca86e0bb1720de0c4","ContentHash":"923b380f52d0af88fbd24c30b6902d84b50cec3a223abd8e11741d420cfafd43","Payload":{"description":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","description_html":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e if the value is not compressed.","signatures":[{"description":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","description_html":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e if the value is not compressed.","description_zh":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 NULL。","description_zh_html":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e。","examples":[],"html":"\u003ccode class=\"function\"\u003epg_column_compression\u003c/code\u003e ( \u003ccode class=\"type\"\u003e\"any\"\u003c/code\u003e ) → \u003ccode class=\"returnvalue\"\u003etext\u003c/code\u003e","returns":"text","text":"pg_column_compression ( \"any\" ) → text","zh_from":"same-version-manual"}]}},"RequestedLocale":"en","Fallback":false,"Versions":["14","15","16","17","18","19","20"],"Locales":["en","zh-Hans"],"Signatures":[{"Version":"18","Ordinal":0,"Hash":"eef7daaa30548528be1208887a31d32f8281323657aadd1849863dd8aa2b821b","Text":"pg_column_compression ( \"any\" ) → text","Returns":"text","Payload":{"description":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns NULL if the value is not compressed.","description_html":"Shows the compression algorithm that was used to compress an individual variable-length value. Returns \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e if the value is not compressed.","description_zh":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 NULL。","description_zh_html":"显示用于压缩单个变长值的压缩算法。如果值没有被压缩，则返回 \u003ccode class=\"literal\"\u003eNULL\u003c/code\u003e。","examples":[],"html":"\u003ccode class=\"function\"\u003epg_column_compression\u003c/code\u003e ( \u003ccode class=\"type\"\u003e\"any\"\u003c/code\u003e ) → \u003ccode class=\"returnvalue\"\u003etext\u003c/code\u003e","returns":"text","text":"pg_column_compression ( \"any\" ) → text","zh_from":"same-version-manual"}}],"Spellings":null,"SQLState":null,"Evidence":null}
