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What are DDL and DML?
...database
DROP – delete objects from the database
TRUNCATE – remove all records from a table, including all spaces allocated for the records are removed
COMMENT – add comments to the data dictionary
RENAME – rename an object
DML
DML is short name of Data Manipulation Lang...
Fastest way to convert string to integer in PHP
... 0.42208
intval("hello"): 0.93678 (222%)
On average, calling intval() is two and a half times slower, and the difference is the greatest if your input already is an integer.
I'd be interested to know why though.
Update: I've run the tests again, this time with coercion (0 + ...
Failed to allocate memory: 8
...e, with 6GB sitting free while the Android emulator tells me that it can't allocate 1GB?
– Strozykowski
Nov 11 '11 at 1:38
5
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What are the different usecases of PNG vs. GIF vs. JPEG vs. SVG?
...ompression: Lossless and Lossy.
Lossless means that the image is made smaller, but at no detriment to the quality.
Lossy means the image is made (even) smaller, but at a detriment to the quality. If you saved an image in a Lossy format over and over, the image quality would get progressively wor...
Dynamic SELECT TOP @var In SQL Server
...
this is great! all this time i thought i had to use dynamic sql.
– Laguna
Feb 20 '12 at 20:09
1
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How to get next/previous record in MySQL?
...IT 1;
edit: Since this answer has been getting a few upvotes lately, I really want to stress the comment I made earlier about understanding that a primary key colum is not meant as a column to sort by, because MySQL does not guarantee that higher, auto incremented, values are necessarily added at ...
Technically, why are processes in Erlang more efficient than OS threads?
...d FPU registers, address space mapping, etc.).
Erlang processes use dynamically allocated stacks, which start very small and grow as necessary. This permits the spawning of many thousands — even millions — of Erlang processes without sucking up all available RAM.
Erlang used to be single-threade...
Full-screen iframe with a height of 100%
Is iframe height=100% supported in all browsers?
17 Answers
17
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AES vs Blowfish for file encryption
...was what became AES.
Interesting aside: at one point in the competition, all the entrants were asked to give their opinion of how the ciphers ranked. It's probably no surprise that each team picked its own entry as the best -- but every other team picked Rijndael as the second best.
That said, th...
How to run a shell script on a Unix console or Mac terminal?
... Then, the script is passed to the program (as second argument) along with all the arguments you gave the script as subsequent arguments.
That means every script that is executable should have a hashbang. If it doesn't, you're not telling the kernel what it is, and therefore the kernel doesn't kno...