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Why are ToLookup and GroupBy different?
...happens when you call ToLookup on an object representing a remote database table with a billion rows in it?
The billion rows are sent over the wire, and you build the lookup table locally.
What happens when you call GroupBy on such an object?
A query object is built; end of story.
When that quer...
When to use nil, blank, empty? [duplicate]
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Here I made this useful table with all the cases
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LINQ Join with Multiple Conditions in On Clause
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This works fine for 2 tables. I have 3 tables and on clause has to link 2 conditions from 3 tables.
My code:
from p in _dbContext.Products
join pv in _dbContext.ProductVariants on p.ProduktId equals pv.ProduktId
join jpr in leftJoinQuery
on new {...
Advantages of Antlr (versus say, lex/yacc/bison) [closed]
...here LL grammars have advantages over LALR grammars.
YACC/Bison generate table driven parsers, which means the "processing logic" is contained in the parser program's data, not so much in the parser's code. The pay off is that even a parser for a very complex language has a relatively small code f...
How do I make a list of data frames?
... data import function for read.csv as appropriate. readr::read_csv or data.table::fread will be faster, or you may also need a different function for a different file type.
Either way, it's handy to name the list elements to match the files
names(my_data) <- gsub("\\.csv$", "", my_files)
# or, ...
Why does ContentResolver.requestSync not trigger a sync?
...ed when it's time to sync. I figure you already have this in place.
4. Establish a binding between an Account-type and a Content Authority
Looking back again at AndroidManifest, that strange <meta-data> tag in our service is the key piece that establishes the binding between a ContentAutho...
Why does my application spend 24% of its life doing a null check?
... other. With the GC heap compacting algorithm otherwise having an unpredictable affect on that. Best to not let me guess at this, measure so you know a fact.
– Hans Passant
May 15 '13 at 11:21
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config.assets.compile=true in Rails production, why not?
...mpiled and fingerprinted to the public/assets. Sprockets returns a mapping table of the plain to fingerprinted filenames to Rails, and Rails writes this to the filesystem. The manifest file (YML in Rails 3 or JSON with a randomised name in Rails 4) is loaded into Memory by Rails at startup and cache...
mysqli_fetch_assoc() expects parameter / Call to a member function bind_param() errors. How to get t
...teraction code right away:
$stmt = $this->con->prepare("INSERT INTO table(name, quantity) VALUES (?,?)");
$stmt->bind_param("si", $name, $quantity);
$stmt->execute();
again, without any conditions around. If an error occurs, it will be treated as any other error in your code. For exam...
UITableView load more when scrolling to bottom like Facebook application
...eloping an application that uses SQLite. I want to show a list of users (UITableView) using a paginating mechanism. Could any one please tell me how to load more data in my list when the user scrolls to the end of the list (like on home page on Facebook application)?
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