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How Pony (ORM) does its tricks?
...s query:
>>> from pony.orm.examples.estore import *
>>> select(c for c in Customer if c.country == 'USA').show()
Which will be translated into the following SQL:
SELECT "c"."id", "c"."email", "c"."password", "c"."name", "c"."country", "c"."address"
FROM "Customer" "c"
WHERE "c"...
What is the use of Enumerable.Zip extension method in Linq?
...rator merges the corresponding elements of two sequences using a specified selector function.
var letters= new string[] { "A", "B", "C", "D", "E" };
var numbers= new int[] { 1, 2, 3 };
var q = letters.Zip(numbers, (l, n) => l + n.ToString());
foreach (var s in q)
Console.WriteLine(s);
Oupu...
How to make rounded percentages add up to 100%
...original,
decimal forceSum, int decimals)
{
var rounded = original.Select(x => Math.Round(x, decimals)).ToList();
Debug.Assert(Math.Round(forceSum, decimals) == forceSum);
var delta = forceSum - rounded.Sum();
if (delta == 0) return rounded;
var deltaUnit = Convert.ToDecim...
Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
...es. Also, not all situations are quite handled- for example, if you try to select from table foo while another transaction is dropping it and creating a replacement table foo, then the blocked transaction will finally receive an error rather than finding the new foo table. (Edit: this was fixed in o...
How can I delete multiple lines in vi?
...
I find this easier
Go VISUAL mode Shift+v
Select lines
d to delete
https://superuser.com/questions/170795/how-can-i-select-and-delete-lines-of-text-in-vi
share
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i...
Read logcat programmatically within application
... // log level: ALL
sCommand.add("*:S"); // ignore logs which are not selected
Process process = new ProcessBuilder().command(sCommand).start();
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
LogCapture mLogCapt...
Build project into a JAR automatically in Eclipse
...con on build.xml.
Step 2
Right-click on the root node in the project.
- Select Properties
- Select Builders
- Select New
- Select Ant Build
- In the Main tab, complete the path to the build.xml file in the bin folder.
Check the Output
The Eclipse output window (named Console) should show...
MySQL Removing Some Foreign keys
...
You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY'
– Gayan Dasanayake
Aug 26 '17 at 2:48
...
How can I get all constants of a type by reflection?
...mp;& !fi.IsInitOnly && fi.FieldType == typeof(T))
.Select(x => (T)x.GetRawConstantValue())
.ToList();
}
}
Then for a class like this
static class MyFruitKeys
{
public const string Apple = "apple";
public const string Plum = "plum";
public con...
Setting the filter to an OpenFileDialog to allow the typical image formats?
...
Complete solution in C# is here:
private void btnSelectImage_Click(object sender, RoutedEventArgs e)
{
// Configure open file dialog box
Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
dlg.Filter = "";
ImageCodecInfo[] codecs = I...