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(Same as \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e.)","description_zh":"提取 bytes 中从第 start 个字节开始的子字符串；若指定了长度，则提取 count 个字节。（与 substring(bytes from start for count) 相同。）","description_zh_html":"提取 \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 个字节开始的子字符串；若指定了长度，则提取 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字节。（与 \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e 相同。）","examples":[{"expr":"substr('\\x1234567890'::bytea, 3, 2)","result":"\\x5678"}],"html":"\u003ccode class=\"function\"\u003esubstr\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\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, \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":"substr ( bytes bytea, start integer [, count integer] ) → bytea","zh_from":"same-version-manual"}]}},"RequestedLocale":"en","Fallback":false,"Versions":["10","11","12","13","14","15","16","17","18","19","20","7.1","7.2","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":"e61e8df5e8c6092778385cea931ec0e7eec8c0646a9507b5c42d1bbadcd6bef8","Text":"substr ( string text, start integer [, count integer] ) → text","Returns":"text","Payload":{"description":"Extracts the substring of string starting at the start'th character, and extending for count characters if that is specified. (Same as substring(string from start for count).)","description_html":"Extracts the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e starting at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th character, and extending for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e characters if that is specified. (Same as \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e.)","description_zh":"提取 string 中从第 start 个字符开始的子字符串；若指定了长度，则提取 count 个字符。（与 substring(string from start for count) 相同。）","description_zh_html":"提取 \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 个字符开始的子字符串；若指定了长度，则提取 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字符。（与 \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e 相同。）","examples":[{"expr":"substr('alphabet', 3)","result":"phabet"},{"expr":"substr('alphabet', 3, 2)","result":"ph"}],"html":"\u003ccode class=\"function\"\u003esubstr\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003estring\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003etext\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, \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":"substr ( string text, start integer [, count integer] ) → text","zh_from":"same-version-manual"}},{"Version":"18","Ordinal":1,"Hash":"ed3dab73b52a875b96bd5d80f85a8de80d2a2ff78a1c56a6a05446ace31dc2a8","Text":"substr ( bytes bytea, start integer [, count integer] ) → bytea","Returns":"bytea","Payload":{"description":"Extracts the substring of bytes starting at the start'th byte, and extending for count bytes if that is specified. (Same as substring(bytes from start for count).)","description_html":"Extracts the substring of \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e starting at the \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e'th byte, and extending for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e bytes if that is specified. (Same as \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e.)","description_zh":"提取 bytes 中从第 start 个字节开始的子字符串；若指定了长度，则提取 count 个字节。（与 substring(bytes from start for count) 相同。）","description_zh_html":"提取 \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 个字节开始的子字符串；若指定了长度，则提取 \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e 个字节。（与 \u003ccode class=\"literal\"\u003esubstring(\u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e from \u003cem class=\"parameter\"\u003e\u003ccode\u003estart\u003c/code\u003e\u003c/em\u003e for \u003cem class=\"parameter\"\u003e\u003ccode\u003ecount\u003c/code\u003e\u003c/em\u003e)\u003c/code\u003e 相同。）","examples":[{"expr":"substr('\\x1234567890'::bytea, 3, 2)","result":"\\x5678"}],"html":"\u003ccode class=\"function\"\u003esubstr\u003c/code\u003e ( \u003cem class=\"parameter\"\u003e\u003ccode\u003ebytes\u003c/code\u003e\u003c/em\u003e \u003ccode class=\"type\"\u003ebytea\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, \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":"substr ( bytes bytea, start integer [, count integer] ) → bytea","zh_from":"same-version-manual"}}],"Spellings":null,"SQLState":null,"Evidence":null}