大约有 22,000 项符合查询结果(耗时:0.0299秒) [XML]

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PostgreSQL Crosstab Query

... the provided input query: row_name, category, value. There is no room for extra columns like in the 2-parameter alternative below. Safe form crosstab(text, text) with 2 input parameters: SELECT * FROM crosstab( 'SELECT section, status, ct FROM tbl ORDER BY 1,2' -- could also ju...
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Send Email Intent

....")); Update: According to marcwjj, it seems that on 4.3, we need to pass string array instead of a string for email address to make it work. We might need to add one more line: intent.putExtra(Intent.EXTRA_EMAIL, addresses); // String[] addresses Ref link ...
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How do I remove the first characters of a specific column in a table?

... - 4) AS MyTrimmedColumn Edit: To explain, RIGHT takes 2 arguments - the string (or column) to operate on, and the number of characters to return (starting at the "right" side of the string). LEN returns the length of the column data, and we subtract four so that our RIGHT function leaves the lef...
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Mapping many-to-many association table with extra column(s)

...ments java.io.Serializable{ private ACId id = new ACId(); private String extra; public AC(){ } public ACId getId() { return id; } public void setId(ACId id) { this.id = id; } public A getA(){ return getId().getA(); } public C...
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What is the best way to tell if a character is a letter or number in Java without using regexes?

What is the best and/or easiest way to recognize if a string.charAt(index) is an A-z letter or a number in Java without using regular expressions? Thanks. ...
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How important is the order of columns in indexes?

...mns involved. Giving that rationale, the only difference is comparing two 'strings' that differ earlier versus later in the string. This is a tiny part of the total cost. There is no "first pass / second pass", as mentioned in one Answer. So, what order should be used? Start with column(s) tested...
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Java Reflection: How to get the name of a variable?

...For example, take this simple class: class TestLocalVarNames { public String aMethod(int arg) { String local1 = "a string"; StringBuilder local2 = new StringBuilder(); return local2.append(local1).append(arg).toString(); } } After compiling with javac -g:vars TestL...
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const char *, char const *, char * const 异同?const修饰符各位置有何区...

const char *, char const *, char * const 异同?const修饰符各位置有何区别?const char * p = new char('a'); 这个是常字符,即p的内容不能被修改。char const * p 意义同上,没有区别。 这时,*...const char * p = new char('a'); 这个是常字符,即p的内容...
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C# equivalent to Java's charAt()?

... we can use the charAt() method in Java get an individual character in a string by specifying its position. Is there an equivalent method in C#? ...
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How to convert a column number (e.g. 127) into an Excel column (e.g. AA)

... Here's how I do it: private string GetExcelColumnName(int columnNumber) { int dividend = columnNumber; string columnName = String.Empty; int modulo; while (dividend > 0) { modulo = (dividend - 1) % 26; columnName ...