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How to get number of rows using SqlDataReader in C#
...reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete OHanlon) the second option is only concurrency-safe when you use a ...
Selecting text in an element (akin to highlighting with your mouse)
I would like to have users click a link, then it selects the HTML text in another element ( not an input).
16 Answers
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Simpler way to put PDB breakpoints in Python code?
...t you'll have to record your own (rather than copy/paste above) as special chars are involved (for escape etc).
– arcseldon
Feb 18 '19 at 6:54
...
How to insert text into the textarea at the current cursor position?
...ction insertAtCursor(myField, myValue) {
//IE support
if (document.selection) {
myField.focus();
sel = document.selection.createRange();
sel.text = myValue;
}
//MOZILLA and others
else if (myField.selectionStart || myField.selectionStart == '0') {
...
How do you find the disk size of a Postgres / PostgreSQL table and its indexes
...
Try the Database Object Size Functions. An example:
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
For all tables, something along the lines of:
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_...
Using IQueryable with Linq
...ram. Your program then filters the data. In essence, the database does a SELECT * FROM Products, and returns EVERY product to you.
With the right IQueryable<T> provider, on the other hand, you can do:
IQueryable<Product> products = myORM.GetQueryableProducts();
var productsOver25 =...
Splitting on first occurrence
...in the list will contain the remainder of the string (inclusive of any sep chars/strings).
– BuvinJ
Sep 10 '19 at 13:01
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How do I put an 'if clause' in an SQL string?
... WHERE purchaseOrder_ID = '@purchaseOrder_ID' and
not exists (SELECT *
FROM itemsOrdered WHERE purchaseOrder_ID = '@purchaseOrdered_ID' AND status = 'PENDING'
)
However, I might guess that you are looping at a higher level. To set all such v...
D3.js: How to get the computed width and height for an arbitrary element?
...d height for an arbitrary g element in my SVG because I need to draw a selection marker around it once the user has clicked it.
...
What is the best way to paginate results in SQL Server
... sake of this example, let's assume that the query you're dealing with is
SELECT * FROM Orders WHERE OrderDate >= '1980-01-01' ORDER BY OrderDate
In this case, you would determine the total number of results using:
SELECT COUNT(*) FROM Orders WHERE OrderDate >= '1980-01-01'
...which may ...