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How do I check to see if a value is an integer in MySQL?
...
I'll assume you want to check a string value. One nice way is the REGEXP operator, matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just tes...
Any way to make a WPF textblock selectable?
...Pointer StartSelectPosition;
TextPointer EndSelectPosition;
public String SelectedText = "";
public delegate void TextSelectedHandler(string SelectedText);
public event TextSelectedHandler TextSelected;
protected override void OnMouseDown(MouseButtonEventArgs e)
{
b...
Escape double quotes in a string
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No.
Either use verbatim string literals as you have, or escape the " using backslash.
string test = "He said to me, \"Hello World\" . How are you?";
The string has not changed in either case - there is a single escaped " in it. This is just a way...
How can I make a JPA OneToOne relation lazy
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private Date createdOn;
@Column(name = "created_by")
private String createdBy;
@OneToOne(fetch = FetchType.LAZY)
@MapsId
private Post post;
public PostDetails() {}
public PostDetails(String createdBy) {
createdOn = new Date();
this.createdBy = cre...
How can I convert JSON to CSV?
... is as easy as using two commands!
pandas.read_json()
To convert a JSON string to a pandas object (either a series or dataframe). Then, assuming the results were stored as df:
df.to_csv()
Which can either return a string or write directly to a csv-file.
Based on the verbosity of previous ans...
Using fonts with Rails asset pipeline
...ore sense than putting them into app/assets/fonts. With
these 2 lines of extra configuration this has worked well for me (on
Rails 4):
app.config.assets.paths << Rails.root.join('vendor', 'assets', 'fonts')
app.config.assets.precompile << /\.(?:svg|eot|woff|ttf)$/
— @jhilden,...
Why are nested weights bad for performance? Alternatives?
...ground="#ffff8800"
android:gravity="center"
android:text="@string/fifty_fifty_text"
android:textColor="@android:color/white"
app:layout_constraintHeight_default="percent"
app:layout_constraintHeight_percent="0.5"
android:textSize="25sp"
app:lay...
What exactly does git's “rebase --preserve-merges” do (and why?)
...e has to define what it means to replay a merge commit, and deal with some extra wrinkles
The most interesting part, conceptually, is perhaps in picking what the new commit's merge parents should be.
Replaying merge commits also require explicitly checking out particular commits (git checkout <...
Angular IE Caching issue for $http
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You can either append a unique querystring (I believe this is what jQuery does with the cache: false option) to the request.
$http({
url: '...',
params: { 'foobar': new Date().getTime() }
})
A perhaps better solution is if you have access to the serv...
How can I concatenate two arrays in Java?
I need to concatenate two String arrays in Java.
61 Answers
61
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