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Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
...
Swift Beta performance: sorting arrays
...amp;x_c, CInt(x_c.count))
let c_stop:UInt64 = mach_absolute_time();
This converts the absolute times to seconds:
static const uint64_t NANOS_PER_USEC = 1000ULL;
static const uint64_t NANOS_PER_MSEC = 1000ULL * NANOS_PER_USEC;
static const uint64_t NANOS_PER_SEC = 1000ULL * NANOS_PER_MSEC;
mach_t...
.toArray(new MyClass[0]) or .toArray(new MyClass[myList.size()])?
... Wow, that was a fast response! Thanks! Yea, I suspected that. Converting to a stream didn't sound efficient. But you never know!
– Pimp Trizkit
Dec 4 '15 at 16:56
2
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Emacs, switch to previous window
...
@phils SHIFT + <keys> meddles with shift selection that is enabled by default from Emacs 23 (shift-selection-mode).
– legends2k
Jul 22 '14 at 12:23
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how to remove only one style property with jquery
I have a div with this property style="-moz-user-select:none; position:static !important;" .
I need to remove the -moz-user-select
Tried with $(selector).css() but I don't know what value to set because it's "none".
...
How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
...
How to make an HTTP POST web request
....
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property ...
How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...