{"Entry":{"collection":"type","key":"varbit","name":"bit varying","aliases":["varbit","varbit [ ( n ) ]"],"metadata":{"aliases":["varbit","varbit [ ( n ) ]"],"category":"Bit strings","content_hash":"14bdfc412551dd12ddefb4ea49b2f3ef0aac3e68f617ea4cb910d2126c04fba4","imported_at":"2026-09-30T00:40:37.055965+08:00","name":"bit varying","name_zh":"","slug":"varbit","summary":"variable-length bit string"}},"Definition":{"Collection":"type","Key":"varbit","SourceDatabase":"center","Version":"18","SourceTable":"data_type","SourceKey":"varbit","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"aliases":["varbit","varbit [ ( n ) ]"],"casts":[{"castcontext":"i","castfunc":"0","castmethod":"b","castsource":"bit","casttarget":"varbit"},{"castcontext":"i","castfunc":"0","castmethod":"b","castsource":"varbit","casttarget":"bit"},{"castcontext":"i","castfunc":"varbit","castmethod":"f","castsource":"varbit","casttarget":"varbit"}],"catalog":{"array_type_name":"_varbit","array_type_oid":"1563","descr":"variable-length bit string","oid":"1562","typacl":"_null_","typalign":"i","typanalyze":"-","typarray":"0","typbasetype":"0","typbyval":"f","typcategory":"V","typcollation":"0","typdefault":"_null_","typdefaultbin":"_null_","typdelim":"','","typelem":"0","typinput":"varbit_in","typisdefined":"t","typispreferred":"t","typlen":"-1","typmodin":"varbittypmodin","typmodout":"varbittypmodout","typname":"varbit","typnamespace":"pg_catalog","typndims":"0","typnotnull":"f","typoutput":"varbit_out","typowner":"POSTGRES","typreceive":"varbit_recv","typrelid":"0","typsend":"varbit_send","typstorage":"x","typsubscript":"-","typtype":"b","typtypmod":"-1"},"comparison_data":{"aliases":["varbit","varbit [ ( n ) ]"],"casts":[{"castcontext":"i","castfunc":"0","castmethod":"b","castsource":"bit","casttarget":"varbit"},{"castcontext":"i","castfunc":"0","castmethod":"b","castsource":"varbit","casttarget":"bit"},{"castcontext":"i","castfunc":"varbit","castmethod":"f","castsource":"varbit","casttarget":"varbit"}],"catalog":{"array_type_name":"_varbit","typacl":"_null_","typalign":"i","typanalyze":"-","typarray":"_varbit","typbasetype":"0","typbyval":"f","typcategory":"V","typcollation":"0","typdefault":"_null_","typdefaultbin":"_null_","typdelim":",","typelem":"0","typinput":"varbit_in","typisdefined":"t","typispreferred":"t","typlen":"-1","typmodin":"varbittypmodin","typmodout":"varbittypmodout","typname":"varbit","typndims":"0","typnotnull":"f","typoutput":"varbit_out","typreceive":"varbit_recv","typrelid":"0","typsend":"varbit_send","typstorage":"x","typsubscript":"-","typtype":"b","typtypmod":"-1"},"facts":[{"label":"Catalog name","value":"pg_catalog.varbit"},{"label":"Declared length","value":"Variable length (varlena)"},{"label":"Input function","value":"varbit_in"},{"label":"Output function","value":"varbit_out"},{"label":"Storage strategy","value":"extended"},{"label":"Type OID","value":"1562"},{"label":"Type kind","value":"Base type"}],"operator_classes":[{"opcdefault":"t","opcfamily":"brin/varbit_minmax_ops","opcintype":"varbit","opckeytype":"varbit","opcmethod":"brin","opcname":"varbit_minmax_ops"},{"opcdefault":"t","opcfamily":"btree/varbit_ops","opcintype":"varbit","opckeytype":"0","opcmethod":"btree","opcname":"varbit_ops"}],"operators":[{"oprcanhash":"f","oprcanmerge":"f","oprcode":"bitcat","oprcom":"0","oprjoin":"-","oprkind":"b","oprleft":"varbit","oprname":"||","oprnegate":"0","oprrest":"-","oprresult":"varbit","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitge","oprcom":"\u003c=(varbit,varbit)","oprjoin":"scalargejoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003e=","oprnegate":"\u003c(varbit,varbit)","oprrest":"scalargesel","oprresult":"bool","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitgt","oprcom":"\u003c(varbit,varbit)","oprjoin":"scalargtjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003e","oprnegate":"\u003c=(varbit,varbit)","oprrest":"scalargtsel","oprresult":"bool","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitle","oprcom":"\u003e=(varbit,varbit)","oprjoin":"scalarlejoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c=","oprnegate":"\u003e(varbit,varbit)","oprrest":"scalarlesel","oprresult":"bool","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitlt","oprcom":"\u003e(varbit,varbit)","oprjoin":"scalarltjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c","oprnegate":"\u003e=(varbit,varbit)","oprrest":"scalarltsel","oprresult":"bool","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitne","oprcom":"\u003c\u003e(varbit,varbit)","oprjoin":"neqjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c\u003e","oprnegate":"=(varbit,varbit)","oprrest":"neqsel","oprresult":"bool","oprright":"varbit"},{"oprcanhash":"f","oprcanmerge":"t","oprcode":"varbiteq","oprcom":"=(varbit,varbit)","oprjoin":"eqjoinsel","oprkind":"b","oprleft":"varbit","oprname":"=","oprnegate":"\u003c\u003e(varbit,varbit)","oprrest":"eqsel","oprresult":"bool","oprright":"varbit"}],"ranges":[]},"comparison_hash":"ea69ecd921b01732802f1f44f376456a29b0a4ab58663c96b5371739517f674f","coverage":"source inventory; exact declared input types for operator classes","description":["variable-length bit string"],"facts":[{"label":"Catalog name","value":"pg_catalog.varbit"},{"label":"Type OID","value":"1562"},{"label":"Type kind","value":"Base type"},{"label":"Declared length","value":"Variable length (varlena)"},{"label":"Storage strategy","value":"extended"},{"label":"Input function","value":"varbit_in"},{"label":"Output function","value":"varbit_out"}],"manual_documentation":"dedicated family chapter","manual_html":"\u003cdiv class=\"sect1\" id=\"DATATYPE-BIT\"\u003e\n\u003cdiv class=\"titlepage\"\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ch2 class=\"title\"\u003e8.10. Bit String Types \u003c/h2\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eBit strings are strings of 1's and 0's. They can be used to store or visualize bit masks. There are two SQL bit types: \u003ccode class=\"type\"\u003ebit(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e and \u003ccode class=\"type\"\u003ebit varying(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, where \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e is a positive integer.\u003c/p\u003e\n\u003cp\u003e\u003ccode class=\"type\"\u003ebit\u003c/code\u003e type data must match the length \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e exactly; it is an error to attempt to store shorter or longer bit strings. \u003ccode class=\"type\"\u003ebit varying\u003c/code\u003e data is of variable length up to the maximum length \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e; longer strings will be rejected. Writing \u003ccode class=\"type\"\u003ebit\u003c/code\u003e without a length is equivalent to \u003ccode class=\"literal\"\u003ebit(1)\u003c/code\u003e, while \u003ccode class=\"type\"\u003ebit varying\u003c/code\u003e without a length specification means unlimited length.\u003c/p\u003e\n\u003cdiv class=\"note\"\u003e\n\u003ch3 class=\"title\"\u003eNote\u003c/h3\u003e\n\u003cp\u003eIf one explicitly casts a bit-string value to \u003ccode class=\"type\"\u003ebit(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated or zero-padded on the right to be exactly \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits, without raising an error. Similarly, if one explicitly casts a bit-string value to \u003ccode class=\"type\"\u003ebit varying(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated on the right if it is more than \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits.\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eRefer to \u003ca class=\"xref\" href=\"/docs/18/sql-syntax-lexical.html#SQL-SYNTAX-BIT-STRINGS\" title=\"4.1.2.5. Bit-String Constants\"\u003eSection 4.1.2.5\u003c/a\u003e for information about the syntax of bit string constants. Bit-logical operators and string manipulation functions are available; see \u003ca class=\"xref\" href=\"/docs/18/functions-bitstring.html\" title=\"9.6. Bit String Functions and Operators\"\u003eSection 9.6\u003c/a\u003e.\u003c/p\u003e\n\u003cdiv class=\"example\" id=\"id-1.5.7.18.7\"\u003e\n\u003cp class=\"title\"\u003e\u003cstrong\u003eExample 8.3. Using the Bit String Types\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"example-contents\"\u003e\n\u003cpre class=\"programlisting\"\u003eCREATE TABLE test (a BIT(3), b BIT VARYING(5));\nINSERT INTO test VALUES (B'101', B'00');\nINSERT INTO test VALUES (B'10', B'101');\n\u003ccode class=\"computeroutput\"\u003e\nERROR:  bit string length 2 does not match type bit(3)\n\u003c/code\u003e\nINSERT INTO test VALUES (B'10'::bit(3), B'101');\nSELECT * FROM test;\n\u003ccode class=\"computeroutput\"\u003e\n  a  |  b\n-----+-----\n 101 | 00\n 100 | 101\n\u003c/code\u003e\n\u003c/pre\u003e\n\u003c/div\u003e\n\u003c/div\u003e\u003cbr class=\"example-break\"\u003e\n\u003cp\u003eA bit string value requires 1 byte for each group of 8 bits, plus 5 or 8 bytes overhead depending on the length of the string (but long values may be compressed or moved out-of-line, as explained in \u003ca class=\"xref\" href=\"/docs/18/datatype-character.html\" title=\"8.3. Character Types\"\u003eSection 8.3\u003c/a\u003e for character strings).\u003c/p\u003e\n\u003c/div\u003e","manual_path":"datatype-bit.html","operator_classes":[{"opcdefault":"t","opcfamily":"btree/varbit_ops","opcintype":"varbit","opckeytype":"0","opcmethod":"btree","opcname":"varbit_ops","opcnamespace":"pg_catalog","opcowner":"POSTGRES"},{"opcdefault":"t","opcfamily":"brin/varbit_minmax_ops","opcintype":"varbit","opckeytype":"varbit","opcmethod":"brin","opcname":"varbit_minmax_ops","opcnamespace":"pg_catalog","opcowner":"POSTGRES"}],"operators":[{"descr":"concatenate","oid":"1797","oprcanhash":"f","oprcanmerge":"f","oprcode":"bitcat","oprcom":"0","oprjoin":"-","oprkind":"b","oprleft":"varbit","oprname":"||","oprnamespace":"pg_catalog","oprnegate":"0","oprowner":"POSTGRES","oprrest":"-","oprresult":"varbit","oprright":"varbit"},{"descr":"equal","oid":"1804","oprcanhash":"f","oprcanmerge":"t","oprcode":"varbiteq","oprcom":"=(varbit,varbit)","oprjoin":"eqjoinsel","oprkind":"b","oprleft":"varbit","oprname":"=","oprnamespace":"pg_catalog","oprnegate":"\u003c\u003e(varbit,varbit)","oprowner":"POSTGRES","oprrest":"eqsel","oprresult":"bool","oprright":"varbit"},{"descr":"not equal","oid":"1805","oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitne","oprcom":"\u003c\u003e(varbit,varbit)","oprjoin":"neqjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c\u003e","oprnamespace":"pg_catalog","oprnegate":"=(varbit,varbit)","oprowner":"POSTGRES","oprrest":"neqsel","oprresult":"bool","oprright":"varbit"},{"descr":"less than","oid":"1806","oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitlt","oprcom":"\u003e(varbit,varbit)","oprjoin":"scalarltjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c","oprnamespace":"pg_catalog","oprnegate":"\u003e=(varbit,varbit)","oprowner":"POSTGRES","oprrest":"scalarltsel","oprresult":"bool","oprright":"varbit"},{"descr":"greater than","oid":"1807","oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitgt","oprcom":"\u003c(varbit,varbit)","oprjoin":"scalargtjoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003e","oprnamespace":"pg_catalog","oprnegate":"\u003c=(varbit,varbit)","oprowner":"POSTGRES","oprrest":"scalargtsel","oprresult":"bool","oprright":"varbit"},{"descr":"less than or equal","oid":"1808","oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitle","oprcom":"\u003e=(varbit,varbit)","oprjoin":"scalarlejoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003c=","oprnamespace":"pg_catalog","oprnegate":"\u003e(varbit,varbit)","oprowner":"POSTGRES","oprrest":"scalarlesel","oprresult":"bool","oprright":"varbit"},{"descr":"greater than or equal","oid":"1809","oprcanhash":"f","oprcanmerge":"f","oprcode":"varbitge","oprcom":"\u003c=(varbit,varbit)","oprjoin":"scalargejoinsel","oprkind":"b","oprleft":"varbit","oprname":"\u003e=","oprnamespace":"pg_catalog","oprnegate":"\u003c(varbit,varbit)","oprowner":"POSTGRES","oprrest":"scalargesel","oprresult":"bool","oprright":"varbit"}],"ranges":[],"related":[{"label":"pg_type catalog","url":"/wiki/catalog/pg_type/?v=18"},{"label":"pg_cast catalog","url":"/wiki/catalog/pg_cast/?v=18"},{"label":"pg_operator catalog","url":"/wiki/catalog/pg_operator/?v=18"},{"label":"pg_opclass catalog","url":"/wiki/catalog/pg_opclass/?v=18"},{"label":"Arrays","url":"/wiki/type/arrays/?v=18"},{"label":"brin index access method","url":"/wiki/indexam/brin/?v=18"},{"label":"btree index access method","url":"/wiki/indexam/btree/?v=18"}],"release":{"channel":"stable","label":"18.6","major":"18","manual_sha256":{"arrays.html":"0e1d5c5a7b4a949d4439995f44f74ad4264e050d16eb9ad2a850fbaee04032df","catalog-pg-type.html":"ea9c9313bab8e92a7da18ebc50c7ff1f908dd80999a7e0ca3bbc82ba626c58d4","datatype-binary.html":"0c03ec47b76e37888a3da7f5dcfd340128a5d356642a85185cc9ebe17856a904","datatype-bit.html":"c49124aad561636c18080b9e09572fde7785a6b9eae86f5a33283f0fd6774c37","datatype-boolean.html":"b633f663e6c8276e7056287640c413aa79dbc15d5353cee0d41653d58d376956","datatype-character.html":"c73eebe413ea709a7792e4cfc3cfe9fb68cb496ebe83c3ebaa9d09f8c40d0f73","datatype-datetime.html":"e366275d8b13845bfa4ef0d68faa093e5f3ecb708a1ec870cbcbf7e425b85699","datatype-enum.html":"cab38e53222e30cc94b24de4b33634fd22d7c93f58ebcf35f646c9b8da78fae8","datatype-geometric.html":"0eb3053cfe7d6b0a4b5592c5d7af8d97cae527e87f063c5793413bcba5c14cd9","datatype-json.html":"650162a05b660146b500a205d523374d00aee117a6a6240d30262be51b6e33e5","datatype-money.html":"8b29c14b90679683ac5c472b59a0a7e2853f32cc7db43fab417b2697a6879964","datatype-net-types.html":"96846e641cc37727ddcd8b8a1aa0dbe33cd9787760a2b4efb0dcb9403d5be63f","datatype-numeric.html":"b74619f7ac2f1ca9f85c48073df78c33dd30e464e61baba6008634534edcb500","datatype-oid.html":"8b3360302225f08ae72716ce1804596de95b568e5d31f788cb4597427b28cc38","datatype-pg-lsn.html":"339172f5107cc7eb7139bec911277647219e92a532cebd0f3da0a5dacf8195af","datatype-pseudo.html":"c7cf0b8214304bd8702c95f2142671ae5f0d631f83717f9c07d9e1f2579961b4","datatype-textsearch.html":"4b15e05be8b49a71b28aea22f2c46d0dbf639a91e7b4fe129a4c737c6daad47c","datatype-uuid.html":"292b307b3223c6182bdba687e7f69e6dca9038430143ad79d56327f6ed4c3246","datatype-xml.html":"061fc2295b7b69be704f0a741b8decd10ad721059f871fb0243c669bb54d7822","datatype.html":"e581f67c74e42006289638c8659e9b338adbfd7f068bd8bf2b3be3880fcd2254","domains.html":"82d486973ccc35d14276627a67ac76b434452f23f9ed4d8aa3fbb01fdf285fc2","functions-info.html":"78ac80bf81da2e4f4a33f3b850faa86f0f58ec54a083d6c31da557907de0df87","rangetypes.html":"e4960abc7ce8e51d794f94f1e57b099d30b7f75dd7f2b23a960eef91f6291c33","rowtypes.html":"74f99e029c3a9edfd3e18810ba3c8cb66d3aada91eb67b86476560871e6617e9","sql-createdomain.html":"e94f927196de1b0ea1ce35cd4603c1f6f544439adcc0edf1c4222358e832245b"},"ref":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","source_files":{"doc/src/sgml/datatype.sgml":"86328daa77e20d81d222376ec0306d9841a17104e436c08d138eb763aefb3700","src/include/catalog/pg_am.dat":"b3cb86b102a42fb0024cbd99779c9897afb40d12a71f5cc5a0e5aee7ff2f9969","src/include/catalog/pg_am.h":"3426799df799f32163fcc0765f43dbdb5e88e626acf31284fef9fc6014b69d8e","src/include/catalog/pg_cast.dat":"97911281ca2c81917394ccb2ec13367e37c6801fd461d5e1a3d2f28b911b46b2","src/include/catalog/pg_cast.h":"de585c7df687d698e7d1d100dce8a794ac9da52414ea48169191019178c8f053","src/include/catalog/pg_opclass.dat":"4ee7d3619a6aa106e1c0db55de903931c7d11b1c60ba053a022519c55f8ee668","src/include/catalog/pg_opclass.h":"9c218537806c8ef0398302faaca7f91315dfc1198c48706cebffb479b68defaf","src/include/catalog/pg_operator.dat":"5d35b9b2ef5f9797cc815263927ef8a12367fedace53e828b4e8b320e2a7f703","src/include/catalog/pg_operator.h":"621b18cfffe102413d79b746ce7a10f77fc60fdd097bac34c22b31070d3ee3c4","src/include/catalog/pg_opfamily.dat":"3b694879027b858f2ecf1fa1152b7e30c6e15a216ba99c2384291c30e9d52311","src/include/catalog/pg_opfamily.h":"e1f5fc8aebd3042df847455bf66bf755f768c2aa8a9b03d22f7ec8563eba59c0","src/include/catalog/pg_proc.dat":"1f934ce80d460159dda137714374a35f9896315ea2476709cbb4da13b38ef95a","src/include/catalog/pg_proc.h":"f7d59f07c5b95e2f3c7141762a0f576e8a3af7581ba54c27537f4d500472bea5","src/include/catalog/pg_range.dat":"5c2271f8e89e9378d1887204e5785060b77405b5f0ff3e6c719250c9c1dcfcc4","src/include/catalog/pg_range.h":"45546d952b5181f989bd9234721897fc2b37005c8e49ce2ddc156f26974c3ca4","src/include/catalog/pg_type.dat":"5f5887b75677cba2d4a1a0cfeb355df5ed91f85d385fac88bd8d7c605b3578f9","src/include/catalog/pg_type.h":"8fb198749fd82b6c1818a3c18455f226f66116fcfeb3d4959c65ce3fda22802e"},"source_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"},"sections":[],"signature":"bit varying [ ( n ) ]","sources":[{"label":"PostgreSQL 18 English manual","path":"datatype-bit.html","sha256":"c49124aad561636c18080b9e09572fde7785a6b9eae86f5a33283f0fd6774c37","url":"/docs/18/datatype-bit.html"},{"label":"Matching PostgreSQL source archive","sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}]},"ManualEvidence":{"manual_path":"datatype-bit.html","release":{"channel":"stable","label":"18.6","major":"18","manual_sha256":{"arrays.html":"0e1d5c5a7b4a949d4439995f44f74ad4264e050d16eb9ad2a850fbaee04032df","catalog-pg-type.html":"ea9c9313bab8e92a7da18ebc50c7ff1f908dd80999a7e0ca3bbc82ba626c58d4","datatype-binary.html":"0c03ec47b76e37888a3da7f5dcfd340128a5d356642a85185cc9ebe17856a904","datatype-bit.html":"c49124aad561636c18080b9e09572fde7785a6b9eae86f5a33283f0fd6774c37","datatype-boolean.html":"b633f663e6c8276e7056287640c413aa79dbc15d5353cee0d41653d58d376956","datatype-character.html":"c73eebe413ea709a7792e4cfc3cfe9fb68cb496ebe83c3ebaa9d09f8c40d0f73","datatype-datetime.html":"e366275d8b13845bfa4ef0d68faa093e5f3ecb708a1ec870cbcbf7e425b85699","datatype-enum.html":"cab38e53222e30cc94b24de4b33634fd22d7c93f58ebcf35f646c9b8da78fae8","datatype-geometric.html":"0eb3053cfe7d6b0a4b5592c5d7af8d97cae527e87f063c5793413bcba5c14cd9","datatype-json.html":"650162a05b660146b500a205d523374d00aee117a6a6240d30262be51b6e33e5","datatype-money.html":"8b29c14b90679683ac5c472b59a0a7e2853f32cc7db43fab417b2697a6879964","datatype-net-types.html":"96846e641cc37727ddcd8b8a1aa0dbe33cd9787760a2b4efb0dcb9403d5be63f","datatype-numeric.html":"b74619f7ac2f1ca9f85c48073df78c33dd30e464e61baba6008634534edcb500","datatype-oid.html":"8b3360302225f08ae72716ce1804596de95b568e5d31f788cb4597427b28cc38","datatype-pg-lsn.html":"339172f5107cc7eb7139bec911277647219e92a532cebd0f3da0a5dacf8195af","datatype-pseudo.html":"c7cf0b8214304bd8702c95f2142671ae5f0d631f83717f9c07d9e1f2579961b4","datatype-textsearch.html":"4b15e05be8b49a71b28aea22f2c46d0dbf639a91e7b4fe129a4c737c6daad47c","datatype-uuid.html":"292b307b3223c6182bdba687e7f69e6dca9038430143ad79d56327f6ed4c3246","datatype-xml.html":"061fc2295b7b69be704f0a741b8decd10ad721059f871fb0243c669bb54d7822","datatype.html":"e581f67c74e42006289638c8659e9b338adbfd7f068bd8bf2b3be3880fcd2254","domains.html":"82d486973ccc35d14276627a67ac76b434452f23f9ed4d8aa3fbb01fdf285fc2","functions-info.html":"78ac80bf81da2e4f4a33f3b850faa86f0f58ec54a083d6c31da557907de0df87","rangetypes.html":"e4960abc7ce8e51d794f94f1e57b099d30b7f75dd7f2b23a960eef91f6291c33","rowtypes.html":"74f99e029c3a9edfd3e18810ba3c8cb66d3aada91eb67b86476560871e6617e9","sql-createdomain.html":"e94f927196de1b0ea1ce35cd4603c1f6f544439adcc0edf1c4222358e832245b"},"ref":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","source_files":{"doc/src/sgml/datatype.sgml":"86328daa77e20d81d222376ec0306d9841a17104e436c08d138eb763aefb3700","src/include/catalog/pg_am.dat":"b3cb86b102a42fb0024cbd99779c9897afb40d12a71f5cc5a0e5aee7ff2f9969","src/include/catalog/pg_am.h":"3426799df799f32163fcc0765f43dbdb5e88e626acf31284fef9fc6014b69d8e","src/include/catalog/pg_cast.dat":"97911281ca2c81917394ccb2ec13367e37c6801fd461d5e1a3d2f28b911b46b2","src/include/catalog/pg_cast.h":"de585c7df687d698e7d1d100dce8a794ac9da52414ea48169191019178c8f053","src/include/catalog/pg_opclass.dat":"4ee7d3619a6aa106e1c0db55de903931c7d11b1c60ba053a022519c55f8ee668","src/include/catalog/pg_opclass.h":"9c218537806c8ef0398302faaca7f91315dfc1198c48706cebffb479b68defaf","src/include/catalog/pg_operator.dat":"5d35b9b2ef5f9797cc815263927ef8a12367fedace53e828b4e8b320e2a7f703","src/include/catalog/pg_operator.h":"621b18cfffe102413d79b746ce7a10f77fc60fdd097bac34c22b31070d3ee3c4","src/include/catalog/pg_opfamily.dat":"3b694879027b858f2ecf1fa1152b7e30c6e15a216ba99c2384291c30e9d52311","src/include/catalog/pg_opfamily.h":"e1f5fc8aebd3042df847455bf66bf755f768c2aa8a9b03d22f7ec8563eba59c0","src/include/catalog/pg_proc.dat":"1f934ce80d460159dda137714374a35f9896315ea2476709cbb4da13b38ef95a","src/include/catalog/pg_proc.h":"f7d59f07c5b95e2f3c7141762a0f576e8a3af7581ba54c27537f4d500472bea5","src/include/catalog/pg_range.dat":"5c2271f8e89e9378d1887204e5785060b77405b5f0ff3e6c719250c9c1dcfcc4","src/include/catalog/pg_range.h":"45546d952b5181f989bd9234721897fc2b37005c8e49ce2ddc156f26974c3ca4","src/include/catalog/pg_type.dat":"5f5887b75677cba2d4a1a0cfeb355df5ed91f85d385fac88bd8d7c605b3578f9","src/include/catalog/pg_type.h":"8fb198749fd82b6c1818a3c18455f226f66116fcfeb3d4959c65ce3fda22802e"},"source_sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"},"sources":[{"label":"PostgreSQL 18 English manual","path":"datatype-bit.html","sha256":"c49124aad561636c18080b9e09572fde7785a6b9eae86f5a33283f0fd6774c37","url":"/docs/18/datatype-bit.html"},{"label":"Matching PostgreSQL source archive","sha256":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","url":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2"}]},"MeasuredEvidence":{}},"Text":{"Collection":"type","Key":"varbit","SourceDatabase":"center","Version":"18","Locale":"en","Title":"bit varying","Summary":"variable-length bit string","BodyHTML":"\u003cdiv id=\"DATATYPE-BIT\"\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ch2\u003e8.10. Bit String Types \u003c/h2\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eBit strings are strings of 1\u0026#39;s and 0\u0026#39;s. They can be used to store or visualize bit masks. There are two SQL bit types: \u003ccode\u003ebit(\u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e and \u003ccode\u003ebit varying(\u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, where \u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e is a positive integer.\u003c/p\u003e\n\u003cp\u003e\u003ccode\u003ebit\u003c/code\u003e type data must match the length \u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e exactly; it is an error to attempt to store shorter or longer bit strings. \u003ccode\u003ebit varying\u003c/code\u003e data is of variable length up to the maximum length \u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e; longer strings will be rejected. Writing \u003ccode\u003ebit\u003c/code\u003e without a length is equivalent to \u003ccode\u003ebit(1)\u003c/code\u003e, while \u003ccode\u003ebit varying\u003c/code\u003e without a length specification means unlimited length.\u003c/p\u003e\n\u003cdiv\u003e\n\u003ch3\u003eNote\u003c/h3\u003e\n\u003cp\u003eIf one explicitly casts a bit-string value to \u003ccode\u003ebit(\u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated or zero-padded on the right to be exactly \u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits, without raising an error. Similarly, if one explicitly casts a bit-string value to \u003ccode\u003ebit varying(\u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated on the right if it is more than \u003cem\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits.\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eRefer to \u003ca href=\"/docs/18/sql-syntax-lexical.html#SQL-SYNTAX-BIT-STRINGS\" rel=\"nofollow\"\u003eSection 4.1.2.5\u003c/a\u003e for information about the syntax of bit string constants. Bit-logical operators and string manipulation functions are available; see \u003ca href=\"/docs/18/functions-bitstring.html\" rel=\"nofollow\"\u003eSection 9.6\u003c/a\u003e.\u003c/p\u003e\n\u003cdiv id=\"id-1.5.7.18.7\"\u003e\n\u003cp\u003e\u003cstrong\u003eExample 8.3. Using the Bit String Types\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv\u003e\n\u003cpre\u003eCREATE TABLE test (a BIT(3), b BIT VARYING(5));\nINSERT INTO test VALUES (B\u0026#39;101\u0026#39;, B\u0026#39;00\u0026#39;);\nINSERT INTO test VALUES (B\u0026#39;10\u0026#39;, B\u0026#39;101\u0026#39;);\n\u003ccode\u003e\nERROR:  bit string length 2 does not match type bit(3)\n\u003c/code\u003e\nINSERT INTO test VALUES (B\u0026#39;10\u0026#39;::bit(3), B\u0026#39;101\u0026#39;);\nSELECT * FROM test;\n\u003ccode\u003e\n  a  |  b\n-----+-----\n 101 | 00\n 100 | 101\n\u003c/code\u003e\n\u003c/pre\u003e\n\u003c/div\u003e\n\u003c/div\u003e\u003cbr\u003e\n\u003cp\u003eA bit string value requires 1 byte for each group of 8 bits, plus 5 or 8 bytes overhead depending on the length of the string (but long values may be compressed or moved out-of-line, as explained in \u003ca href=\"/docs/18/datatype-character.html\" rel=\"nofollow\"\u003eSection 8.3\u003c/a\u003e for character strings).\u003c/p\u003e\n\u003c/div\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"0eab571d0e109af0decd0c0da22b2f36f872c231d576005e5e8611a7085acd28","Payload":{"description":["variable-length bit string"],"manual_html":"\u003cdiv class=\"sect1\" id=\"DATATYPE-BIT\"\u003e\n\u003cdiv class=\"titlepage\"\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ch2 class=\"title\"\u003e8.10. Bit String Types \u003c/h2\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eBit strings are strings of 1's and 0's. They can be used to store or visualize bit masks. There are two SQL bit types: \u003ccode class=\"type\"\u003ebit(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e and \u003ccode class=\"type\"\u003ebit varying(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, where \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e is a positive integer.\u003c/p\u003e\n\u003cp\u003e\u003ccode class=\"type\"\u003ebit\u003c/code\u003e type data must match the length \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e exactly; it is an error to attempt to store shorter or longer bit strings. \u003ccode class=\"type\"\u003ebit varying\u003c/code\u003e data is of variable length up to the maximum length \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e; longer strings will be rejected. Writing \u003ccode class=\"type\"\u003ebit\u003c/code\u003e without a length is equivalent to \u003ccode class=\"literal\"\u003ebit(1)\u003c/code\u003e, while \u003ccode class=\"type\"\u003ebit varying\u003c/code\u003e without a length specification means unlimited length.\u003c/p\u003e\n\u003cdiv class=\"note\"\u003e\n\u003ch3 class=\"title\"\u003eNote\u003c/h3\u003e\n\u003cp\u003eIf one explicitly casts a bit-string value to \u003ccode class=\"type\"\u003ebit(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated or zero-padded on the right to be exactly \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits, without raising an error. Similarly, if one explicitly casts a bit-string value to \u003ccode class=\"type\"\u003ebit varying(\u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e, it will be truncated on the right if it is more than \u003cem class=\"replaceable\"\u003e\u003ccode\u003en\u003c/code\u003e\u003c/em\u003e bits.\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eRefer to \u003ca class=\"xref\" href=\"/docs/18/sql-syntax-lexical.html#SQL-SYNTAX-BIT-STRINGS\" title=\"4.1.2.5. Bit-String Constants\"\u003eSection 4.1.2.5\u003c/a\u003e for information about the syntax of bit string constants. Bit-logical operators and string manipulation functions are available; see \u003ca class=\"xref\" href=\"/docs/18/functions-bitstring.html\" title=\"9.6. Bit String Functions and Operators\"\u003eSection 9.6\u003c/a\u003e.\u003c/p\u003e\n\u003cdiv class=\"example\" id=\"id-1.5.7.18.7\"\u003e\n\u003cp class=\"title\"\u003e\u003cstrong\u003eExample 8.3. Using the Bit String Types\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"example-contents\"\u003e\n\u003cpre class=\"programlisting\"\u003eCREATE TABLE test (a BIT(3), b BIT VARYING(5));\nINSERT INTO test VALUES (B'101', B'00');\nINSERT INTO test VALUES (B'10', B'101');\n\u003ccode class=\"computeroutput\"\u003e\nERROR:  bit string length 2 does not match type bit(3)\n\u003c/code\u003e\nINSERT INTO test VALUES (B'10'::bit(3), B'101');\nSELECT * FROM test;\n\u003ccode class=\"computeroutput\"\u003e\n  a  |  b\n-----+-----\n 101 | 00\n 100 | 101\n\u003c/code\u003e\n\u003c/pre\u003e\n\u003c/div\u003e\n\u003c/div\u003e\u003cbr class=\"example-break\"\u003e\n\u003cp\u003eA bit string value requires 1 byte for each group of 8 bits, plus 5 or 8 bytes overhead depending on the length of the string (but long values may be compressed or moved out-of-line, as explained in \u003ca class=\"xref\" href=\"/docs/18/datatype-character.html\" title=\"8.3. Character Types\"\u003eSection 8.3\u003c/a\u003e for character strings).\u003c/p\u003e\n\u003c/div\u003e","related":[{"label":"pg_type catalog","url":"/wiki/catalog/pg_type/?v=18"},{"label":"pg_cast catalog","url":"/wiki/catalog/pg_cast/?v=18"},{"label":"pg_operator catalog","url":"/wiki/catalog/pg_operator/?v=18"},{"label":"pg_opclass catalog","url":"/wiki/catalog/pg_opclass/?v=18"},{"label":"Arrays","url":"/wiki/type/arrays/?v=18"},{"label":"brin index access method","url":"/wiki/indexam/brin/?v=18"},{"label":"btree index access method","url":"/wiki/indexam/btree/?v=18"}],"sections":[]}},"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}