{"Entry":{"collection":"lock","key":"for-share","name":"FOR SHARE","aliases":[],"metadata":{"abbrev":"FS","content_hash":"993634bb64d779949a28a84b488e522ef56f378d5563d8e158472062118268a9","imported_at":"2026-09-27T17:58:01.270403+08:00","name":"FOR SHARE","name_zh":"FOR SHARE","position":9,"scope":"row","slug":"for-share","source_rev":"10:f4e8f137bfb08a664c8288824c1e36b5143ac875;11:170e416034ec0231d9e9238f2577eeb76ca8d181;12:3f302f0ed06f69c5ebd33d4df95895323a3cbef6;13:05f6c9ec2c475fae8fdd56ae40bd01afcf70d1f2;14:fba35c7c28a567839faba867db0808564c0a66db;15:0351991b8e7c7b64382e2f30ce581a8f276590a6;16:dcc37b7099a9f3cf2c75167d8dc92e75f96bc1fa;17:163288afd32a448244c8df75b3c33181aadd7f20;18:753057e340da8f22e57c9a409ea7a235fd6a46bd;19:b73d13c32c834a2c8e1c60cb92f79530376cedf1;20:2c10c2ce4d7bcd57543a49ab402af02a39724e0a","summary":"Behaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE."}},"Definition":{"Collection":"lock","Key":"for-share","SourceDatabase":"center","Version":"18","SourceTable":"lock_mode","SourceKey":"for-share","SourceRevision":"10:f4e8f137bfb08a664c8288824c1e36b5143ac875;11:170e416034ec0231d9e9238f2577eeb76ca8d181;12:3f302f0ed06f69c5ebd33d4df95895323a3cbef6;13:05f6c9ec2c475fae8fdd56ae40bd01afcf70d1f2;14:fba35c7c28a567839faba867db0808564c0a66db;15:0351991b8e7c7b64382e2f30ce581a8f276590a6;16:dcc37b7099a9f3cf2c75167d8dc92e75f96bc1fa;17:163288afd32a448244c8df75b3c33181aadd7f20;18:753057e340da8f22e57c9a409ea7a235fd6a46bd;19:b73d13c32c834a2c8e1c60cb92f79530376cedf1;20:2c10c2ce4d7bcd57543a49ab402af02a39724e0a","Facts":{"commands":[{"label":"SELECT FOR SHARE","note":"Lock selected rows, with ROW SHARE on the target table. NOWAIT and SKIP LOCKED affect waiting, not mode compatibility.","slug":"select","source":{"kind":"documentation","path":"doc/src/sgml/mvcc.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"4b7bf77ee0af4b86052330ff2421d567df3604b75fe7d4f522bec84fdea87340","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/mvcc.sgml"},"source_url":"https://www.postgresql.org/docs/18/explicit-locking.html","variant":"8b3c78ad3c64"}],"conflicts":["for-no-key-update","for-update"],"description":["Behaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE."],"provenance":{"doc_slug":"18","fetched_at":"2026-09-27T09:39:42+00:00","label":"18","major":"18","official_url":"https://www.postgresql.org/docs/18/explicit-locking.html","ref":"REL_18_STABLE","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sources":[{"kind":"command-documentation","path":"doc/src/sgml/ref/alter_index.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"746cd43287186dfbfa6acf77fd5c6713e66919653fb00af5476a0baa65988e7a","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/alter_index.sgml"},{"kind":"command-documentation","path":"doc/src/sgml/ref/alter_table.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"10436673fa2f093bdf51986a06d22dd748a9bb003bcd5517db2a65fba569a3c9","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/alter_table.sgml"},{"kind":"command-documentation","path":"doc/src/sgml/ref/comment.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"d0048329d237192696d7ccb9471aba4137d943556fdb770e2ffb3cf6c511c18f","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/comment.sgml"},{"kind":"source","path":"src/backend/commands/copy.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"f50ecc1531109fc172d841d461e209cef611f3d017ef4184034c39e128deabbe","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/commands/copy.c"},{"kind":"command-documentation","path":"doc/src/sgml/ref/create_index.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"3698f11c6f447d127e4624a1a845dee4d5146b8337ddc6d895a7962e676717f8","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/create_index.sgml"},{"kind":"source","path":"src/backend/access/heap/heapam.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"bca2ca0746a1862016bdb416b8482441a7b16360f71afe5e4abf6dbae0fa0c72","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/access/heap/heapam.c"},{"kind":"source","path":"src/backend/catalog/index.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"98a4156a5c21ae856a3b583b633cdeb578a5b69910386c9f166d69fcb04ba2d0","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/catalog/index.c"},{"kind":"command-documentation","path":"doc/src/sgml/ref/insert.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"f93403779fb1d980cd5995a1e2741bbdae8404584407610f9aba33ec4724a39f","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/insert.sgml"},{"kind":"source","path":"src/backend/storage/lmgr/lock.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"e7f43560bf6a8417ff46991238084b6edeb44a995b87670ed1f7fa6f1515276b","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/storage/lmgr/lock.c"},{"kind":"documentation","path":"doc/src/sgml/mvcc.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"4b7bf77ee0af4b86052330ff2421d567df3604b75fe7d4f522bec84fdea87340","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/mvcc.sgml"},{"kind":"command-documentation","path":"doc/src/sgml/ref/reindex.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"5e889d6e1d9b09d5f9cd3f7086ca13f540da0fe8262cdd8a9037ce9aa6f1dfdf","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/reindex.sgml"},{"kind":"source","path":"src/backend/utils/adt/ri_triggers.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"a3fed49fbda88fe0fe5bcf35eb019fced28596ae4046233f2acb2eb9f90ab1da","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/utils/adt/ri_triggers.c"},{"kind":"source","path":"src/backend/commands/tablecmds.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"df8817816f893e73d5648fea169e222ba33320e5b24bf755b424b29098f4e7da","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/commands/tablecmds.c"},{"kind":"command-documentation","path":"doc/src/sgml/ref/vacuum.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"80ca5592cda7b74938385f84f09faac33574374c1a05d605a2d55982e4cf1bbf","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/ref/vacuum.sgml"},{"kind":"source","path":"src/backend/access/heap/vacuumlazy.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"90932e3b1a7b57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similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE."},"ManualEvidence":{"sources":[{"kind":"documentation","path":"doc/src/sgml/mvcc.sgml","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"4b7bf77ee0af4b86052330ff2421d567df3604b75fe7d4f522bec84fdea87340","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/doc/src/sgml/mvcc.sgml"},{"kind":"source","path":"src/backend/storage/lmgr/lock.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"e7f43560bf6a8417ff46991238084b6edeb44a995b87670ed1f7fa6f1515276b","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/storage/lmgr/lock.c"},{"kind":"source","path":"src/backend/access/heap/heapam.c","revision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","sha256":"bca2ca0746a1862016bdb416b8482441a7b16360f71afe5e4abf6dbae0fa0c72","url":"https://raw.githubusercontent.com/postgres/postgres/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/access/heap/heapam.c"}]},"MeasuredEvidence":{}},"Text":{"Collection":"lock","Key":"for-share","SourceDatabase":"center","Version":"18","Locale":"en","Title":"FOR SHARE","Summary":"Behaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE.","BodyHTML":"\u003cp\u003eBehaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE.\u003c/p\u003e","SourceRevision":"10:f4e8f137bfb08a664c8288824c1e36b5143ac875;11:170e416034ec0231d9e9238f2577eeb76ca8d181;12:3f302f0ed06f69c5ebd33d4df95895323a3cbef6;13:05f6c9ec2c475fae8fdd56ae40bd01afcf70d1f2;14:fba35c7c28a567839faba867db0808564c0a66db;15:0351991b8e7c7b64382e2f30ce581a8f276590a6;16:dcc37b7099a9f3cf2c75167d8dc92e75f96bc1fa;17:163288afd32a448244c8df75b3c33181aadd7f20;18:753057e340da8f22e57c9a409ea7a235fd6a46bd;19:b73d13c32c834a2c8e1c60cb92f79530376cedf1;20:2c10c2ce4d7bcd57543a49ab402af02a39724e0a","ContentHash":"d3d6dc03cfda748e74f11766928126e071555d402836705f6865fa6c57d7ec62","Payload":{"description":["Behaves similarly to FOR NO KEY UPDATE, except that it acquires a shared lock rather than exclusive lock on each retrieved row. A shared lock blocks other transactions from performing UPDATE, DELETE, SELECT FOR UPDATE or SELECT FOR NO KEY UPDATE on these rows, but it does not prevent them from performing SELECT FOR SHARE or SELECT FOR KEY SHARE."]}},"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}