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Check if a row exists, otherwise insert
...cedure that updates a row in a table. If the row doesn't exist, insert it. All this steps wrapped by a transaction.
11 Ans...
MySQL, update multiple tables with one query
...ookID is very important, without it The Books table update would happen to all rows and not only for the row with the specified id. Some lessons are learned the hard way, this one was learned in the terrifing way.
– nheimann1
Mar 24 '15 at 15:06
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Determine command line working directory when running node bin script
I am creating a node command line interface. It is installed globally and uses a bin file to execute.
5 Answers
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How can I get the count of milliseconds since midnight for the current?
... // Get current moment in UTC, then…
.get( ChronoField.MILLI_OF_SECOND ) // interrogate a `TemporalField`.
2017-04-25T03:01:14.113Z → 113
Get the fractional second in nanoseconds (billions).
Divide by a thousand to truncate to milliseconds (thousands).
See this code run l...
async/await - when to return a Task vs void?
...
1) Normally, you would want to return a Task. The main exception should be when you need to have a void return type (for events). If there's no reason to disallow having the caller await your task, why disallow it?
2) async methods...
Find running median from a stream of integers
...based solution works is explained below:
For the first two elements add smaller one to the maxHeap on the left, and bigger one to the minHeap on the right. Then process stream data one by one,
Step 1: Add next item to one of the heaps
if next item is smaller than maxHeap root add it to maxHea...
Why is super.super.method(); not allowed in Java?
...t's fine - RedItems can always be confident that the items it contains are all red. Now suppose we were able to call super.super.add():
public class NaughtyItems extends RedItems
{
@Override
public void add(Item item)
{
// I don't care if it's red or not. Take that, RedItems!
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Get record counts for all tables in MySQL database
Is there a way to get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
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How to make the division of 2 ints produce a float instead of another int?
...ppens before the division.
The other operand will be effectively automatically cast to a float by the compiler because the rules say that if either operand is of floating point type then the operation will be a floating point operation, even if the other operand is integral. Java Language Specific...
How do I break out of nested loops in Java?
...ption (sorry). But I'd still be unhappy about this if it wasn't obvious (small loops, warning comment if the label/break still aren't visible enough).
– Steve314
Dec 7 '11 at 0:40
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