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SQLite UPSERT / UPDATE OR INSERT
... Why is that a bad thing? And if the data hasn't changed, why are you calling UPSERT in the first place? But even so, it's a good thing the update happens, setting Changes=1 or else the INSERT statement would incorrectly fire, which you don't want it to.
– Mark A. Donohoe...
What does send() do in Ruby?
...l some method reacts (because its name matches the first argument).
Practically speaking, those lines are equivalent:
1.send '+', 2
1.+(2)
1 + 2
Note that send bypasses visibility checks, so that you can call private methods, too (useful for unit testing).
If there is really no variable befor...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
... you want to use the plural version of your table name in the rename_table call.
– Han
Sep 20 '12 at 5:37
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Difference between “read commited” and “repeatable read”
...nd it could see different rows based on COMMITTED only B writing. could we call it Simple Lock?
RepeatableRead: Transaction B will read the same data (rows) whatever Transaction A is doing. But Transaction A can change other rows. Rows level Block
Serialisable: Transaction B will read the same rows ...
Refresh image with a new one at the same url
..." + new Date().getTime();
This will append the current timestamp automatically when you are creating the image, and it will make the browser look again for the image instead of retrieving the one in the cache.
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Importing variables from another file?
...le1.x1 have the same value, they are not the same variables. For instance, call a function in file1 that modifies x1 and then try to print the variable from the main file: you will not see the modified value.
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Get button click inside UITableViewCell
... sure your buttons tag is set. You really don't want to mix up your action calling. Either do it through IB or do it explicitly in your code.
– Sententia
Apr 29 '14 at 7:12
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LINQ to SQL - Left Outer Join with multiple join conditions
...
You need to introduce your join condition before calling DefaultIfEmpty(). I would just use extension method syntax:
from p in context.Periods
join f in context.Facts on p.id equals f.periodid into fg
from fgi in fg.Where(f => f.otherid == 17).DefaultIfEmpty()
where p.c...
When should I use require() and when to use define()?
...tion (the function passed to define()), until there has been a require([]) call that has asked for it, or something that depends on it." github.com/jrburke/requirejs/wiki/…
– alxndr
Aug 18 '14 at 16:55
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How to declare a variable in MySQL?
...* FROM places WHERE place BETWEEN start AND finish;
END; //
DELIMITER ;
CALL sp_test(5);
If the DEFAULT clause is missing, the initial value is NULL.
The scope of a local variable is the BEGIN ... END block within
which it is declared.
Server System Variables (prefixed with @@):
The MySQL se...