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If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 string 中从第 start 个字符开始、长度为 count 个字符的子字符串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 个字符开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字符的子字符串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay('Txxxxas' placing 'hom' from 2 for 4)","result":"Thomas"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003etext\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003etext\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003etext\u003c/code\u003e","returns":"text","text":"overlay ( string text PLACING newsubstring text FROM start integer [FOR count integer] ) → text","zh_from":"same-version-manual"},{"description":"Replaces the substring of bytes that starts at the start'th byte and extends for count bytes with newsubstring. If count is omitted, it defaults to the length of newsubstring.","description_html":"Replaces the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e that starts at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th byte and extends for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e bytes with \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e. If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 bytes 中从第 start 个字节开始、长度为 count 个字节的子字符串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 个字节开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字节的子字符串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay('\\x1234567890'::bytea placing '\\002\\003'::bytea from 2 for 3)","result":"\\x12020390"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003ebytea\u003c/code\u003e","returns":"bytea","text":"overlay ( bytes bytea PLACING newsubstring bytea FROM start integer [FOR count integer] ) → bytea","zh_from":"same-version-manual"},{"description":"Replaces the substring of bits that starts at the start'th bit and extends for count bits with newsubstring. If count is omitted, it defaults to the length of newsubstring.","description_html":"Replaces the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e that starts at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th bit and extends for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e bits with \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e. If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 bits 中从第 start 位开始、长度为 count 位的子串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 位开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 位的子串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay(B'01010101010101010' placing B'11111' from 2 for 3)","result":"0111110101010101010"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebit\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebit\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003ebit\u003c/code\u003e","returns":"bit","text":"overlay ( bits bit PLACING newsubstring bit FROM start integer [FOR count integer] ) → bit","zh_from":"same-version-manual"}]}},"RequestedLocale":"en","Fallback":false,"Versions":["10","11","12","13","14","15","16","17","18","19","20","7.3","7.4","8.0","8.1","8.2","8.3","8.4","9.0","9.1","9.2","9.3","9.4","9.5","9.6"],"Locales":["en","zh-Hans"],"Signatures":[{"Version":"18","Ordinal":0,"Hash":"b79f1e9b1f830d6bd8ca7315099018103620c57486c62ed0def8d792fd3753a0","Text":"overlay ( string text PLACING newsubstring text FROM start integer [FOR count integer] ) → text","Returns":"text","Payload":{"description":"Replaces the substring of string that starts at the start'th character and extends for count characters with newsubstring. If count is omitted, it defaults to the length of newsubstring.","description_html":"Replaces the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e that starts at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th character and extends for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e characters with \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e. If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 string 中从第 start 个字符开始、长度为 count 个字符的子字符串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 个字符开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字符的子字符串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay('Txxxxas' placing 'hom' from 2 for 4)","result":"Thomas"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003etext\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003etext\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003etext\u003c/code\u003e","returns":"text","text":"overlay ( string text PLACING newsubstring text FROM start integer [FOR count integer] ) → text","zh_from":"same-version-manual"}},{"Version":"18","Ordinal":1,"Hash":"bf9a2c1c719759486f2141fb8bfa9d864f00d0ccd0b73a8ce1db27dd300b41cb","Text":"overlay ( bytes bytea PLACING newsubstring bytea FROM start integer [FOR count integer] ) → bytea","Returns":"bytea","Payload":{"description":"Replaces the substring of bytes that starts at the start'th byte and extends for count bytes with newsubstring. If count is omitted, it defaults to the length of newsubstring.","description_html":"Replaces the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e that starts at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th byte and extends for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e bytes with \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e. If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 bytes 中从第 start 个字节开始、长度为 count 个字节的子字符串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 个字节开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字节的子字符串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay('\\x1234567890'::bytea placing '\\002\\003'::bytea from 2 for 3)","result":"\\x12020390"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003ebytea\u003c/code\u003e","returns":"bytea","text":"overlay ( bytes bytea PLACING newsubstring bytea FROM start integer [FOR count integer] ) → bytea","zh_from":"same-version-manual"}},{"Version":"18","Ordinal":2,"Hash":"f74b4df4d2aa38ad7a219c45e031861497e6015ac41967ad6737db5900769382","Text":"overlay ( bits bit PLACING newsubstring bit FROM start integer [FOR count integer] ) → bit","Returns":"bit","Payload":{"description":"Replaces the substring of bits that starts at the start'th bit and extends for count bits with newsubstring. If count is omitted, it defaults to the length of newsubstring.","description_html":"Replaces the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e that starts at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th bit and extends for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e bits with \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e. If \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e is omitted, it defaults to the length of \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e.","description_zh":"用 newsubstring 替换 bits 中从第 start 位开始、长度为 count 位的子串。如果省略 count，则默认为 newsubstring 的长度。","description_zh_html":"用 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 替换 \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e 中从第 \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e 位开始、长度为 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 位的子串。如果省略 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e，则默认为 \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e 的长度。","examples":[{"expr":"overlay(B'01010101010101010' placing B'11111' from 2 for 3)","result":"0111110101010101010"}],"html":"\u003ccode class=\"function\"\u003eoverlay\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebits\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebit\u003c/code\u003e \u003ccode class=\"literal\"\u003ePLACING\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003enewsubstring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebit\u003c/code\u003e \u003ccode class=\"literal\"\u003eFROM\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e [\u003cspan class=\"optional\"\u003e\u003ccode class=\"literal\"\u003eFOR\u003c/code\u003e \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003einteger\u003c/code\u003e\u003c/span\u003e] ) → \u003ccode class=\"returnvalue\"\u003ebit\u003c/code\u003e","returns":"bit","text":"overlay ( bits bit PLACING newsubstring bit FROM start integer [FOR count integer] ) → bit","zh_from":"same-version-manual"}}],"Spellings":null,"SQLState":null,"Evidence":null}