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What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...
TEXT and CHAR will convert to/from the character set they have associated with time. BLOB and BINARY simply store bytes.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings ...
How can I cast int to enum?
...urEnum is dynamic and will only be known at runtime, and what I want is to convert to Enum?
– Shimmy Weitzhandler
Feb 19 '12 at 9:56
235
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Media Queries: How to target desktop, tablet, and mobile?
...1281px) { /* hi-res laptops and desktops */ }
In practice, many designers convert pixels to ems, largely because ems afford better zooming. At standard zoom 1em === 16px, multiply pixels by 1em/16px to get ems. For example, 320px === 20em.
In response to the comment, min-width is standard in "mobil...
How do I create a unique constraint that also allows nulls?
...R TABLE dbo.Party ADD SamAccountNameUnique
AS (Coalesce(SamAccountName, Convert(varchar(11), PartyID)))
ALTER TABLE dbo.Party ADD CONSTRAINT UQ_Party_SamAccountName
UNIQUE (SamAccountNameUnique)
You simply have to put something in the computed column that will be guaranteed unique across the...
How to deserialize a list using GSON or another JSON library in Java?
... hassle with the Type object, and if you really need a list you can always convert the array to a list, e.g.:
List<Video> videoList = Arrays.asList(videoArray);
IMHO this is much more readable.
In Kotlin this looks like this:
Gson().fromJson(jsonString, Array<Video>::class.java)
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Real mouse position in canvas [duplicate]
...lient window you'll have to subtract the position of the canvas element to convert it relative to the element itself.
Example of integration in your code:
//put this outside the event loop..
var canvas = document.getElementById("imgCanvas");
var context = canvas.getContext("2d");
function draw(ev...
What is time_t ultimately a typedef to?
... values are usually only stored in memory, not on disk. Instead, time_t is converted to text or some other portable format for persistent storage. That makes the Y2038 problem to not really be a problem.
– user25148
Jan 23 '09 at 19:21
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How can I add remote repositories in Mercurial?
... to mercurial, I would like to use only one tool for my source management. Convert once the repository build the appropriate structures and then only mercurial commands for production. I am kind of aware that both git and mercurial can collaborate but never tried it.
– topless
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What's the difference between “Request Payload” vs “Form Data” as seen in Chrome dev tools Network t
... as a plain string because json is essentially a string. you can of course convert it into a standard "object" with json_encode but that doesn't make it a "json object" either.
– Volkan Ulukut
Dec 7 '16 at 11:32
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