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How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SE...
What's the difference between lists and tuples?
...e pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store notes on locations. A list on the other hand could be used to store multiple locations. Naturally one might want to ad...
What are conventions for filenames in Go?
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There's a few guidelines to follow.
File names that begin with "." or "_" are ignored by the go tool
Files with the suffix _test.go are only compiled and run by the go test tool.
Files with os and architecture specific suffixes automatically follow those same constraints, e.g. name_linux.go will...
What does the brk() system call do?
...rge (say, >128K) allocations. See, for instance, the discussion of MMAP_THRESHOLD in the Linux malloc(3) manpage.
– zwol
Aug 9 '11 at 15:26
1
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How to deep copy a list?
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E0_copy is not a deep copy. You don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operat...
Extract file name from path, no matter what the os/path format
...asename will be empty, so make your own function to deal with it:
def path_leaf(path):
head, tail = ntpath.split(path)
return tail or ntpath.basename(head)
Verification:
>>> paths = ['a/b/c/', 'a/b/c', '\\a\\b\\c', '\\a\\b\\c\\', 'a\\b\\c',
... 'a/b/../../a/b/c/', 'a/b/../....
How to properly reuse connection to Mongodb across NodeJs application and modules
...re( 'mongodb' ).MongoClient;
const url = "mongodb://localhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );...
How do I convert a String object into a Hash object?
... different string, you can do it without using dangerous eval method:
hash_as_string = "{\"0\"=>{\"answer\"=>\"1\", \"value\"=>\"No\"}, \"1\"=>{\"answer\"=>\"2\", \"value\"=>\"Yes\"}, \"2\"=>{\"answer\"=>\"3\", \"value\"=>\"No\"}, \"3\"=>{\"answer\"=>\"4\", \"value\...
How do I get the directory that a program is running from?
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How about add char pBuf[256]; size_t len = sizeof(pBuf); to let the solution more clearly.
– charles.cc.hsu
Oct 5 '16 at 13:22
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UITableView load more when scrolling to bottom like Facebook application
...sBatchOfItems = try MyDataHelper.findRange(start..<end)
} catch _ {
print("query failed")
}
// update UITableView with new batch of items on main thread after query finishes
DispatchQueue.main.async {
if let newItems = thisBatchOfItems {
...