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Should try…catch go inside or outside a loop?
...ch structures are placed. Internally, they are implemented as a code-range table in a structure that is created when the method is called. While the method is executing, the try/catch structures are completely out of the picture unless a throw occurs, then the location of the error is compared again...
MySQL with Node.js
...qlx.getSession('mysqlx://localhost:33060')
.then(session => {
const table = session.getSchema('testSchema').getTable('testTable');
// The criteria is defined through the expression.
return table.update().where('name = "bar"').set('age', 50)
.execute()
.then(() => {...
Sending a message to nil in Objective-C
...gt; 0 )
or this:
return [myArray count]; // say for number of rows in a table
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Decompressing GZip Stream from HTTPClient Response
...w HttpClient();
HttpResponseMessage response;
DataSet dsTable = new DataSet();
try
{
//Gets the headers that should be sent with each request
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"))...
Dynamic SELECT TOP @var In SQL Server
...
SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
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Omit rows containing specific column of NA
...
It is possible to use na.omit for data.table:
na.omit(data, cols = c("x", "z"))
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Postgresql: Conditionally unique constraint
... a constraint which enforces uniqueness on a column only in a portion of a table.
2 Answers
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Subset of rows containing NA (missing) values in a chosen column of a data frame
...t "NA" strings to NA values, and let "NULL" strings as is).
If using read.table() or read.csv(), you should consider the "na.strings" argument to do clean data import, and always work with real R NA values.
An example, working in both cases "NULL" and "NA" cells :
DF <- read.csv("file.csv", na...
Which @NotNull Java annotation should I use?
...nt approaches. Some packages use JLS 9.6.4.1 style contexts. The following table gives an overview:
FIELD METHOD PARAMETER LOCAL_VARIABLE
android.support.annotation X X X
edu.umd.cs.findbugs.annotations X X X X
org.jetbra...
Is there an opposite to display:none?
...
When changing element's display in Javascript, in many cases a suitable option to 'undo' the result of element.style.display = "none" is element.style.display = "". This removes the display declaration from the style attribute, reverting the actual value of display property to the value set...