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PDO Prepared Inserts multiple rows in single query
... table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
if($count > 0){
for($x=0; $x<$count; $x++){
$re...
How to turn on/off ReactJS 'development mode'?
...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV ...
How can I write output from a unit test?
Any call in my unit tests to either Debug.Write(line) or Console.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
...
If you want to insert all the columns then
insert into def select * from abc;
here the number of columns in def should be equal to abc.
if you want to insert the subsets of columns then
insert into def (col1,col2, col3 ) select scol1,scol2,...
Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
Publish-Subscribe
The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
Wrap a delegate in an IEqualityComparer
...fying. But I still don't understand your hashing policy of t => 0. If all objects always hash to the same thing (zero), then isn't that even more broken than using obj.GetHashCode, per @Dan Tao's point? Why not always force the caller to provide a good hash function?
– Jo...
How to track down a “double free or corruption” error
...
If you're using glibc, you can set the MALLOC_CHECK_ environment variable to 2, this will cause glibc to use an error tolerant version of malloc, which will cause your program to abort at the point where the double free is done.
You can set this from gdb by using ...
How to add Google Analytics Tracking ID to GitHub Pages
... I have added them, however Google analytics say the Tracking is not installed. My page as specified in G-Analytics is http://avi-aryan.github.io
– Avi
Jul 15 '13 at 12:33
1
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What is the difference between 'my' and 'our' in Perl?
...
On the other hand, our variables are package variables, and thus automatically:
global variables
definitely not private
not necessarily new
can be accessed outside the package (or lexical scope) with the
qualified namespace, as $package_name::variable.
Declaring a variable with our allows you...
Querying DynamoDB by date
...
Updated Answer:
DynamoDB allows for specification of secondary indexes to aid in this sort of query. Secondary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist w...