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Count number of records returned by group by
...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically.
– Joe Aldrich
Sep 20 '17 at 13:33
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What __init__ and self do on Python?
...to declare it explicitly. When you create an instance of the A class and call its methods, it will be passed automatically, as in ...
a = A() # We do not pass any argument to the __init__ method
a.method_a('Sailor!') # We only pass a single argument
The __init__ method is roughly w...
How does !!~ (not not tilde/bang bang tilde) alter the result of a 'contains/included' Array method
... a shorter way to do
$.inArray("foo", bar) !== -1
$.inArray returns the index of the item in the array if the first argument is found, and it returns -1 if its not found. This means that if you're looking for a boolean of "is this value in the array?", you can't do a boolean comparison, since -1 ...
How to get current route in Symfony 2?
... not a route. As such, Symfony doesn't know what route that is for. Typically, you have one route to one controller, so it may seem weird that this can't report anything besides "_internal", however, it is possible to create general-purpose controllers that get associated with more than one route ...
How to print a query string with parameter values when using Hibernate
...he the following categories:
org.hibernate.SQL - set to debug to log all SQL DML statements as they are executed
org.hibernate.type - set to trace to log all JDBC parameters
So a log4j configuration could look like:
# logs the SQL statements
log4j.logger.org.hibernate.SQL=debug
# Logs the...
Why is `std::move` named `std::move`?
The C++11 std::move(x) function doesn't really move anything at all. It is just a cast to r-value. Why was this done? Isn't this misleading?
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What is a “callable”?
...t's clear what a metaclass is , there is an associated concept that I use all the time without knowing what it really means.
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Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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How do I delete a local repository in git? [duplicate]
... do not list removed files
--cached only remove from the index
-f, --force override the up-to-date check
-r allow recursive removal
--ignore-unmatch exit with a zero status even if nothing matched
When I had to do this, deleting the objects and r...
Remove directory which is not empty
...th) {
if (fs.existsSync(path)) {
fs.readdirSync(path).forEach((file, index) => {
const curPath = Path.join(path, file);
if (fs.lstatSync(curPath).isDirectory()) { // recurse
deleteFolderRecursive(curPath);
} else { // delete file
fs.unlinkSync(curPath);
...