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How to get the next auto-increment id in mysql
... Thanks for the first two options.. But the third is just number two called from PHP.. Not sure what makes that faster on large databases...
– Gerard ONeill
Feb 12 '16 at 15:26
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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How to split a large text file into smaller files with equal number of lines?
...a large (by number of lines) plain text file that I'd like to split into smaller files, also by number of lines. So if my file has around 2M lines, I'd like to split it up into 10 files that contain 200k lines, or 100 files that contain 20k lines (plus one file with the remainder; being evenly divi...
appending array to FormData and send via AJAX
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add all type inputs to FormData
const formData = new FormData();
for (let key in form) {
Array.isArray(form[key])
? form[key].forEach(value => formData.append(key + '[]', value))
: formData.append(key, for...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
...e is to assign a dummy column to separate each new table. This works especially well if you're looping through a result set for a list of columns in a scripting language such as Python or PHP.
SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table...
How to write file if parent folder doesn't exist?
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If the whole path already exists, mkdirp is a noop. Otherwise it creates all missing directories for you.
This module does what you want: https://npmjs.org/package/writefile . Got it when googling for "writefile mkdirp". This module returns a promise instead of taking a callback, so be sure to r...
Random record from MongoDB
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Do a count of all records, generate a random number between 0 and the count, and then do:
db.yourCollection.find().limit(-1).skip(yourRandomNumber).next()
share
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How does HTTP file upload work?
...?) always threaded so that they can handle concurrent connections. Essentially, the daemon process that's listening on port 80 immediately hands off the task of serving to another thread/process in order that it can return to listening for another connection; even if two incoming connections arrive...
Iterator invalidation rules
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C++17 (All references are from the final working draft of CPP17 - n4659)
Insertion
Sequence Containers
vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capa...
How would you count occurrences of a string (actually a char) within a string?
...nsion methods on the string class. I guess they figured devs wouldn't want all those extension methods to show up on the string class. Probably a wise decision.
– Judah Gabriel Himango
Feb 15 '09 at 23:27
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