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Omit rows containing specific column of NA
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It is possible to use na.omit for data.table:
na.omit(data, cols = c("x", "z"))
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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(() => {...
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...
Entity Framework - Add Navigation Property Manually
... database and do not have any control over the schema, but there are a few tables that do not have foreign key constraints defined, but there is an implicit relationship defined.
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Dynamic SELECT TOP @var In SQL Server
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SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
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SQL WHERE condition is not equal to?
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You can do like this
DELETE FROM table WHERE id NOT IN ( 2 )
OR
DELETE FROM table WHERE id <> 2
As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not 2(including the NULLs...
JSTL in JSF2 Facelets… makes sense?
...item} is only available during view render time. Same is true for an h:dataTable and similar components.
<c:if>/<c:choose> vs rendered
As another example, this Facelets markup conditionally adding different tags using <c:if> (you can also use <c:choose><c:when><c:o...
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...
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"))...
What's wrong with using == to compare floats in Java?
...lse ensure that no float which compares unequal to itself gets stored in a table. Otherwise, a program which tries to e.g. count how many unique results can be produced from an expression when fed various inputs may regard every NaN value as unique.
– supercat
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