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How to implement a many-to-many relationship in PostgreSQL?
... -- explicit pk
);
I made a few adjustments:
The n:m relationship is normally implemented by a separate table - bill_product in this case.
I added serial columns as surrogate primary keys. In Postgres 10 or later consider an IDENTITY column instead. See:
Safely rename tables using serial primary...
Mysql command not found in OS X 10.7
... through socket '/tmp/mysql.sock' (2)
– SilverNightaFall
May 14 '12 at 4:18
2
This means that the...
Git branch strategy for small dev team [closed]
...branches as "silos" of code, where code in a less stable branch will eventually "graduate" to one considered more stable after testing and general approval by your team.
Step by step, your workflow under this model might look like this:
You need to fix a bug.
Create a branch called myfix that is ...
How to make inline functions in C#
...=> x + y;
void print(int x) { Console.WriteLine(x); }
There are basically two different types for these: Func and Action. Funcs return values but Actions don't. The last type parameter of a Func is the return type; all the others are the parameter types.
There are similar types with different...
Multiple lines of text in UILabel
...
UILineBreakModeWordWrap is actually the default so you don't need the first line.
– Jarred Olson
Jul 30 '12 at 18:23
1
...
Eclipse: have the same file open in two editors?
...r file and then Window->New Editor (Note: in newer versions it will be called New Window)
Then, click on its tab and drag it somewhere else to have two editors of the same file
Update: as mentioned by moschlar, From version 4.4, two editors can be created with Window -> Editor -> Clone.
...
Count number of records returned by group by
...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically.
– Joe Aldrich
Sep 20 '17 at 13:33
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show 3 more comments
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Simulator slow-motion animations are now on?
...that if he's using a beta, he could have pressed shift 3 times and accidentally activated it?
– CodaFi
Dec 25 '11 at 7:44
...
What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...
How to use double or single brackets, parentheses, curly braces
...veral more
Also, brace expansions create lists of strings which are typically iterated over in loops:
$ echo f{oo,ee,a}d
food feed fad
$ mv error.log{,.OLD}
(error.log is renamed to error.log.OLD because the brace expression
expands to "mv error.log error.log.OLD")
$ for num in {000..2}; do ech...