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How big is too big for a PostgreSQL table?
...uch data will exist, test it for your volume and see what you get. Testing one table with 90 million rows may be as easy as:
select x,1 as c2,2 as c3
from generate_series(1,90000000) x;
https://wiki.postgresql.org/wiki/FAQ
Limit Value
Maximum Database Size Unlimited
Maximum Table Size ...
Java “Virtual Machine” vs. Python “Interpreter” parlance?
...ny statically-typed code interactively
would be tedious, so it just isn't done that way.
In the Java world, the virtual machine steals the show because it runs programs
written in a language which can actually be compiled into machine instructions,
and the result is speed and resource efficiency. ...
Good reasons to prohibit inheritance in Java?
...o be extended, and with enough documentation to describe how it should be done
Classes marked final
If you are writing purely internal code this may be a bit of overkill. However the extra effort involved in adding five characters to a class file is very small. If you are writing only for internal...
Use of alloc init instead of new
...ttp://macresearch.org/difference-between-alloc-init-and-new
Some selected ones are:
new doesn't support custom initializers (like initWithString)
alloc-init is more explicit than new
General opinion seems to be that you should use whatever you're comfortable with.
...
Structs versus classes
I'm about to create 100,000 objects in code. They are small ones, only with 2 or 3 properties. I'll put them in a generic list and when they are, I'll loop them and check value a and maybe update value b .
...
What is the proper way to check if a string is empty in Perl?
...
As already mentioned by several people, eq is the right operator here.
If you use warnings; in your script, you'll get warnings about this (and many other useful things); I'd recommend use strict; as well.
...
Scatterplot with marginal histograms in ggplot2
...vote than the correct answer. My understanding is that this is essentially one-dimensional heatmap: the rugs are darker wherever is crowded. My only worry would be, heatmap's resolution is not as high as a histogram. e.g.. when the plot is small, all rugs will be squeezed together, which makes it ha...
How does Facebook Sharer select Images and other metadata when sharing my URL?
...raph meta tags that it looks at to decide which image to show.
The keys one for the Facebook image are:
<meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
and it should be pr...
How to describe “object” arguments in jsdoc?
... can not be used for @returns.
For objects that will be used at more than one point in source
In this case a @typedef comes in very handy. You can define the type at one point in your source and use it as a type for @param or @returns or other JSDoc tags that can make use of a type.
/**
* @typed...
Character Limit in HTML
...
There are 2 main solutions:
The pure HTML one:
<input type="text" id="Textbox" name="Textbox" maxlength="10" />
The JavaScript one (attach it to a onKey Event):
function limitText(limitField, limitNum) {
if (limitField.value.length > limitNum) {
...