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IEnumerable vs List - What to Use? How do they work?
...some doubts over how Enumerators work, and LINQ. Consider these two simple selects:
10 Answers
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Restore LogCat window within Android Studio
...e bottom). Use the "gear" at the extreme top right of the log cat section; select floating mode. Confusingly it then "appears to be docked" still ... just grab the bar and move it around. (If you're used to Mac, it's a little confusing.) (Android Studio is awesome on Mac eh??)
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How to update column with null value
...Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
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Getting attribute using XPath
...e), for
the first element?
Use:
/*/book[1]/title/@lang
This means:
Select the lang attribute of the title element that is a child of the first book child of the top element of the XML document.
To get just the string value of this attribute use the standard XPath function string():
string(...
Cleanest way to build an SQL string in Java
...uild an SQL string to do database manipulation (updates, deletes, inserts, selects, that sort of thing) - instead of the awful string concat method using millions of "+"'s and quotes which is unreadable at best - there must be a better way.
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Postgres NOT in array
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SELECT COUNT(*) FROM "messages" WHERE NOT (3 = ANY (recipient_ids))
You can always negate WHERE (condition) with WHERE NOT (condition)
share
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How to style the with only CSS?
How can I style <option> s of a <select> element with cross-browser compatibility? I know many JavaScript ways which customize the dropdown to convert into <li> , which I'm not asking about.
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What is the difference between bindParam and bindValue?
...iated parameter markers
Example:
$value = 'foo';
$s = $dbh->prepare('SELECT name FROM bar WHERE baz = :baz');
$s->bindParam(':baz', $value); // use bindParam to bind the variable
$value = 'foobarbaz';
$s->execute(); // executed with WHERE baz = 'foobarbaz'
or
$value = 'foo';
$s = $dbh...
How to split a string literal across multiple lines in C / Objective-C?
...de it.
#define QUOTE(...) #__VA_ARGS__
const char *sql_query = QUOTE(
SELECT word_id
FROM table1, table2
WHERE table2.word_id = table1.word_id
ORDER BY table1.word ASC
);
the preprocessor turns this into:
const char *sql_query = "SELECT word_id FROM table1, table2 WHERE table2.wo...
Stash only one file out of multiple files that have changed with Git?
...
You can also use git stash save -p "my commit message". This way you can select which hunks should be added to stash, whole files can be selected as well.
You'll be prompted with a few actions for each hunk:
y - stash this hunk
n - do not stash this hunk
q - quit; do not stash this hun...