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LINQ order by null column where order is ascending and nulls should be last
... descending
orderby p.LowestPrice descending
select p;
will be translated by the compiler to
var products = _context.Products
.Where(p => p.ProductTypeId == 1)
.OrderByDescending(p => p.LowestPrice.HasValue)
...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
...;orWhere($orThose)
->get();
The above will result in such query:
SELECT * FROM users
WHERE (field = value AND another_field = another_value AND ...)
OR (yet_another_field = yet_another_value AND ...)
share
...
Func vs. Action vs. Predicate [duplicate]
...s probably most commonly used in LINQ - for example in projections:
list.Select(x => x.SomeProperty)
or filtering:
list.Where(x => x.SomeValue == someOtherValue)
or key selection:
list.Join(otherList, x => x.FirstKey, y => y.SecondKey, ...)
Action is more commonly used for th...
Booleans, conditional operators and autoboxing
...ave in common; since null (type "the special null type") can be implicitly converted (widened) to any type, you can consider the special null type to be a "superclass" of any type (class) for the purposes of lub().
– Bert F
Apr 25 '14 at 13:03
...
What's the best way to make a d3.js visualisation layout responsive?
...n the window resizes like so:
var aspect = width / height,
chart = d3.select('#chart');
d3.select(window)
.on("resize", function() {
var targetWidth = chart.node().getBoundingClientRect().width;
chart.attr("width", targetWidth);
chart.attr("height", targetWidth / aspect);
});
...
How can I get the current date and time in UTC or GMT in Java?
...ccording to stackoverflow.com/questions/4123534/…, the MySQL JDBC driver converts a given java.util.Timestamp (or java.util.Date) to the server time zone.
– Derek Mahar
Dec 7 '10 at 21:02
...
Correct way to pass multiple values for same parameter name in GET request
...s handle forms by default. For example take a look at the form element <select multiple> and how it handles multiple values from this example at w3schools.
<form action="/action_page.php">
<select name="cars" multiple>
<option value="volvo">Volvo</option>
<optio...
Entity Framework with NOLOCK
...SMS, open a query (#1) and run: CREATE TABLE ##Test(Col1 INT); BEGIN TRAN; SELECT * FROM ##Test WITH (TABLOCK, XLOCK);. Open another query (#2) and run: SELECT * FROM ##Test;. The SELECT won't return as it is being blocked by the still open transaction in tab #1 that is using an exclusive lock. Canc...
How many database indexes is too many?
...
It depends on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since t...
How to find the mysql data directory from command line in windows
... the following command line:
mysql -s -N -uUSER -p information_schema -e 'SELECT Variable_Value FROM GLOBAL_VARIABLES WHERE Variable_Name = "datadir"'
The command will select the value only from mysql's internal information_schema database and disables the tabular output and column headers.
Outp...