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What is the difference between float and double?
...nd the type long double provides at least as much precision as double. The set of values of the type float is a subset of the set of values of the type double; the set of values of the type double is a subset of the set of values of the type long double.
The C++ standard adds:
The value repres...
SQL, Postgres OIDs, What are they and why are they useful?
...EATE TABLE … WITH OIDS command
default_with_oids (boolean) compatibility setting
The data type OID remains in Postgres 12. You can explicitly create a column of the type OID.
After migrating to Postgres 12, any optionally-defined system column oid will no longer be invisible by default. Perfor...
Is it possible to use raw SQL within a Spring Repository
...
The @Query annotation allows to execute native queries by setting the nativeQuery flag to true.
Quote from Spring Data JPA reference docs.
Also, see this section on how to do it with a named native query.
...
git ahead/behind info between master and branch?
... been working like this as long as I remember.
As of version 1.8, you can set the tracking branch like this:
git branch --track test-branch
As of version 1.7, the syntax was different:
git branch --set-upstream test-branch
...
Java `final` method: what does it promise?
... encapsulated data -- look at immutable Objects where their attributes are set at the construction time and should never be changed. Or a calculated value derived from those attributes. A good example is the Java String class.
Reliability and Contract -- Objects are composed of primitives (int, char...
Add missing dates to pandas dataframe
...ex is an amazing function. It can (1) reorder existing data to match a new set of labels, (2) insert new rows where no label previously existed, (3) fill data for missing labels, (including by forward/backward filling) (4) select rows by label!
– unutbu
Oct 11 ...
PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
...hird value of the array, it will contain the value bar because it was just set by the previous iteration of that loop.
Is it a bug?
No. This is the behavior of a referenced item, and not a bug. It would be similar to running something like:
for ($i = 0; $i < count($arr); $i++) { $item = $arr[$i];...
What is the Invariant Culture?
...ber to a string and later parse it back from any computer with any culture set.
// Use some non-invariant culture.
CultureInfo nonInvariantCulture = new CultureInfo("en-US");
Thread.CurrentThread.CurrentCulture = nonInvariantCulture;
decimal dec = 1.1m;
string convertedToString = dec.ToString();
...
Why does this assert throw a format exception when comparing structures?
...ase()
{ Width = width; Height = height; }
public int Width { get; set; }
public int Height { get; set; }
}
[TestMethod]
public void TestMethod1()
{
var test1 = new MyClass(0, 0);
var test2 = new MyClass(1, 1);
Assert.AreEqual(test1, test2, "Show me A [{0}] and B [{1}]", tes...
Add a dependency in Maven
...xml Once saved, my maven directory on hard drive and maven dependency setting in STS is updated within seconds. You can edit the .xml directly, but using the tool may help avoid xml format problems.
– Chris R
Jan 16 '13 at 19:34
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