Let's say we want to replace only numbers with 2 digits: regular expression will find them with (\d\d)
SELECT REGEXP_REPLACE ('2, 5, and 10 are numbers in this example', '(\d\d)', '#')
FROM dual;
Results in:
'2, 5, and # are numbers in this example'
If I want to swap parts of the text, I us...
Use Nested Loops.
Usage : use_nl(A B)
This hint will ask the engine to use nested loop method to join the tables A and B. That is row by row comparison. The hint does not force the order of the join, just asks for NL.
SELECT /*+use_nl(e d)*/ *
FROM Employees E
JOIN Departments D on E.Department...
In the simple example, we simply set the width of the rectangle to that of it's parent. Let's consider a more complicated example:
ApplicationWindow {
visible: true
width: 400
height: 640
Rectangle{
id: rect
anchors.centerIn: parent
height: 100
...
Sample Data:
CREATE TABLE table_name ( id, list ) AS
SELECT 1, 'a,b,c,d' FROM DUAL UNION ALL -- Multiple items in the list
SELECT 2, 'e' FROM DUAL UNION ALL -- Single item in the list
SELECT 3, NULL FROM DUAL UNION ALL -- NULL list
SELECT 4, 'f,,g' FROM DUAL; -- NULL item...
Sample Data:
CREATE TABLE table_name ( id, list ) AS
SELECT 1, 'a,b,c,d' FROM DUAL UNION ALL -- Multiple items in the list
SELECT 2, 'e' FROM DUAL UNION ALL -- Single item in the list
SELECT 3, NULL FROM DUAL UNION ALL -- NULL list
SELECT 4, 'f,,g' FROM DUAL; -- NULL item...
Sample Data:
CREATE TABLE table_name ( id, list ) AS
SELECT 1, 'a,b,c,d' FROM DUAL UNION ALL -- Multiple items in the list
SELECT 2, 'e' FROM DUAL UNION ALL -- Single item in the list
SELECT 3, NULL FROM DUAL UNION ALL -- NULL list
SELECT 4, 'f,,g' FROM DUAL; -- NULL item...
Often people try to index some content and then find it. If they cannot see the expected result, they try to troubleshoot the whole end-to-end process. The better way is to see whether the content actually indexed in the expected fields. This way it splits the problem into two: indexing and searchin...
lock provides thread-safety for a block of code, so that it can be accessed by only one thread within the same process. Example:
private static object _lockObj = new object();
static void Main(string[] args)
{
Task.Run(() => TaskWork());
Task.Run(() => TaskWork());
Task.Run((...
You can implement the swipe-to-dismiss and drag-and-drop features with the RecyclerView without using 3rd party libraries.
Just use the ItemTouchHelper class included in the RecyclerView support library.
Instantiate the ItemTouchHelper with the SimpleCallback callback and depending on which functi...
var dict = ["name": "John", "surname": "Doe"]
// Set the element with key: 'name' to 'Jane'
dict["name"] = "Jane"
print(dict)
<link rel="stylesheet" media="min-width: 600px" href="example.css" />
This stylesheet is still downloaded but is applied only on devices with screen width larger than 600px.
Common table expressions support extracting portions of larger queries. For example:
WITH sales AS (
SELECT
orders.ordered_at,
orders.user_id,
SUM(orders.amount) AS total
FROM orders
GROUP BY orders.ordered_at, orders.user_id
)
SELECT
sales.ordered_at,
sales.total,...
Two Random class created at the same time will have the same seed value.
Using System.Guid.NewGuid().GetHashCode() can get a different seed even in the same time.
Random rnd1 = new Random();
Random rnd2 = new Random();
Console.WriteLine("First 5 random number in rnd1");
for (int i = 0...
Average
The AVG() aggregate function will return the average of values selected.
SELECT AVG(Salary) FROM Employees
Aggregate functions can also be combined with the where clause.
SELECT AVG(Salary) FROM Employees where DepartmentId = 1
Aggregate functions can also be combined with group by ...
There are three visibility types that you can apply to methods (class/object functions) and properties (class/object variables) within a class, which provide access control for the method or property to which they are applied.
You can read extensively about these in the PHP Documentation for OOP Vi...
