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MySQL JOIN the most recent row only?
...ow it makes my queries virtually instantaneous (WorkBench literally says 0.000 seconds, even with sql_no_cache set), whereas doing the search in the join took multiple seconds to complete. Still baffled, but I mean you can't argue with results like that.
– Brian Leishman
...
How to loop through array in jQuery?
...5 elements in total but their indexes are strewn across the range 0 to 150,000 for some reason, and so the length is 150,001), and if you use appropriate safeguards like hasOwnProperty and checking the property name is really numeric (see link above), for..in can be a perfectly reasonable way to avo...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... also much faster on larger DataFrames
df = pd.DataFrame({'a': [1,2,3] * 100000, 'b': [2,3,4] * 100000})
DataFrame created with 300,000 rows
%timeit df["A1"], df["A2"] = calculate(df['a'])
2.65 ms ± 92.4 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
%timeit df["A1"], df["A2"] = zi...
What are sessions? How do they work?
...member, because the lights are all out. What if your teller gives your $10,000 withdrawal to someone else - the wrong person?! It's absolutely vital that the teller can recognise you as the one who made the withdrawal, so that you can get the money (or resource) that you asked for.
Solution:
When yo...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
...)
Inability to make simple queries like LOCK TABLES ( it throws SQLSTATE[HY000]: General error: 2030 This command is not supported in the prepared statement protocol yet exception )
Need to fetch all rows from result or close cursor before next query ( with mysqlnd or emulated prepares it automatica...
What is a “surrogate pair” in Java?
...F, some additional complexity is used to store values above this range (0x10000 to 0x10FFFF). This is done using pairs of code units known as surrogates.
The surrogate code units are in two ranges known as "high surrogates" and "low surrogates", depending on whether they are allowed at the start or...
Why use make over a shell script?
...eclarative(-ish) parallel programming language.
Let's say that you have 4,000 graphic files to convert and 4 CPUs. Try writing a 10-line shell script (I'm being generous here) that will do it reliably while saturating your CPUs.
Perhaps the real question is why do people bother writing shell scrip...
In C#, how do I calculate someone's age based on a DateTime type birthday?
...ob = int.Parse(dateOfBirth.ToString("yyyyMMdd"));
int age = (now - dob) / 10000;
Or alternatively without all the type conversion in the form of an extension method. Error checking omitted:
public static Int32 GetAge(this DateTime dateOfBirth)
{
var today = DateTime.Today;
var a = (today...
Android: textColor of disabled button in selector not showing?
..._enabled="false" android:color="#9D9FA2" />
<item android:color="#000"/>
</selector>
In your style.xml, put a reference to that text_color.xml file as follows:
<style name="buttonStyle" parent="@android:style/Widget.Button">
<item name="android:textStyle">bold</i...
How to Customize a Progress Bar In Android
... <shape>
<gradient
android:startColor="#000001"
android:centerColor="#0b131e"
android:centerY="1.0"
android:endColor="#0d1522"
android:angle="270"
/>
</shape>
</item>
&...