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Why is the use of alloca() not considered good practice?
...of the program's execution.
In the header file:
void DoSomething() {
wchar_t* pStr = alloca(100);
//......
}
In the implementation file:
void Process() {
for (i = 0; i < 1000000; i++) {
DoSomething();
}
}
So what happened was the compiler inlined DoSomething function and a...
Set selected option of select box
I want to set a option that was selected previously to be displayed on page load. I tried it with the following code:
16 An...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
...
You are so close! All you need to do is select BOTH the home and its max date time, then join back to the topten table on BOTH fields:
SELECT tt.*
FROM topten tt
INNER JOIN
(SELECT home, MAX(datetime) AS MaxDateTime
FROM topten
GROUP BY home) groupedtt...
Get an OutputStream into a String
...tring constructor, the codepage can be a String or an instance of java.nio.charset.Charset. A possible value is java.nio.charset.StandardCharsets.UTF_8.
The method toString() accepts only a String as a codepage parameter (stand Java 8).
...
1052: Column 'id' in field list is ambiguous
...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
Subscript and Superscript a String in Android
... HTML, that is creating a Spanned, which TextViews do support. Essentially CharSequences with style information.
– Dandre Allison
Apr 20 '12 at 17:21
1
...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
...
How to exclude this / current / dot folder from find “type d”
...his particular case (.), golfs better than the mindepth solution (24 vs 26 chars), although this is probably slightly harder to type because of the !.
To exclude other directories, this will golf less well and requires a variable for DRYness:
D="long_name"
find "$D" ! -path "$D" -type d
My decis...