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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":"","description_zh_html":"","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":""}},{"Version":"18","Ordinal":2,"Hash":"98b0015d208ad3f5721f7ac6dbace39deb999df5905d05d1276ffd634772e072","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":"","description_zh_html":"","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":""}}],"Spellings":null,"SQLState":null,"Evidence":null}