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Java String split removed empty values
...[] split = data.split("\\|", -1);
Little more details:
split(regex) internally returns result of split(regex, 0) and in documentation of this method you can find (emphasis mine)
The limit parameter controls the number of times the pattern is applied and therefore affects the length of the resultin...
Difference between Select Unique and Select Distinct
... database brands other than Oracle, SELECT UNIQUE may not be recognized at all.
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Regular expression matching a multiline block of text
...)((?:(?:\n|\r\n?).+)+)", re.MULTILINE)
BTW, you don't want to use the DOTALL modifier here; you're relying on the fact that the dot matches everything except newlines.
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Under what conditions is a JSESSIONID created?
...s created/sent when session is created. Session is created when your code calls request.getSession() or request.getSession(true) for the first time. If you just want to get the session, but not create it if it doesn't exist, use request.getSession(false) -- this will return you a session or null. In...
What do hjust and vjust do when making a plot using ggplot?
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I have tried that, and I get Error in grid.Call("L_textBounds", as.graphicsAnnot(x$label), x$x, x$y, : Polygon edge not found (zero-width or zero-height?) for vjust = .72 and higher.
– William Gunn
Sep 3 '11 at 0:48
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What are '$$' used for in PL/pgSQL
...c to function definitions. It can be used to replace single quotes practically anywhere in SQL scripts.
The body of a function happens to be a string literal which has to be enclosed in single quotes. Dollar-quoting is a PostgreSQL-specific substitute for single quotes to avoid quoting issues insi...
SQL, Postgres OIDs, What are they and why are they useful?
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OIDs basically give you a built-in id for every row, contained in a system column (as opposed to a user-space column). That's handy for tables where you don't have a primary key, have duplicate rows, etc. For example, if you have a t...
How to remove all subviews of a view in Swift?
I'm looking for a simple method to remove at once all subviews from a superview instead of removing them one by one.
20 Ans...
Changing the maximum length of a varchar column?
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You need
ALTER TABLE YourTable ALTER COLUMN YourColumn <<new_datatype>> [NULL | NOT NULL]
But remember to specify NOT NULL explicitly if desired.
ALTER TABLE YourTable ALTER COLUMN YourColumn VARCHAR (500) NOT NULL;
If you leave it unspecified as below...
ALTER TABLE Your...
load and execute order of scripts
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If you aren't dynamically loading scripts or marking them as defer or async, then scripts are loaded in the order encountered in the page. It doesn't matter whether it's an external script or an inline script - they are executed in the order the...